focal (1) testssl.1.gz

Provided by: testssl.sh_3.0+dfsg1-1_all bug

NAME

       testssl

NAME

       testssl.sh -- check encryption of SSL/TLS servers

SYNOPSIS

       testssl.sh [OPTIONS] <URI>, testssl.sh [OPTIONS] --file <FILE>

       or

       testssl.sh [BANNER OPTIONS]

DESCRIPTION

       testssl.sh  is  a  free  command line tool which checks a server´s service on any port for the support of
       TLS/SSL ciphers, protocols as well as cryptographic flaws and much more.

       The output rates findings by color (screen) or severity (file output)  so  that  you  are  able  to  tell
       whether something is good or bad. The (screen) output has several sections in which classes of checks are
       being performed. To ease readability on the screen it aligns and indents the output properly.

       Only you see the result. You also can use it internally on your LAN. Except DNS  lookups  or  unless  you
       instruct  testssl.sh to check for revocation of certificates it doesn´t use any other hosts or even third
       parties for any test.

REQUIREMENTS

       Testssl.sh is out of the box portable:  it  runs  under  any  Unix-like  stack:  Linux,  *BSD,  MacOS  X,
       WSL=Windows  Subsystem  for  Linux,  Cygwin  and  MSYS2.  bash is a prerequisite, also version 3 is still
       supported. Standard utilities like awk, sed, tr and head are also needed. This can be of a BSD, System  5
       or GNU flavor whereas grep from System V is not yet supported.

       Any  OpenSSL  or  LibreSSL  version  is needed as a helper. Unlike previous versions of testssl.sh almost
       every check is done via (TCP) sockets. In addition statically linked OpenSSL binaries for major operating
       systems are supplied in ./bin/.

GENERAL

       testssl.sh URI as the default invocation does the so-called default run which does a number of checks and
       puts out the results colorized (ANSI and termcap) on the screen. It does every check listed below  except
       -E which are (order of appearance):

       0)  displays  a  banner  (see  below),  does  a DNS lookup also for further IP addresses and does for the
       returned IP address a reverse lookup. Last but not least a service check is being done.

       1) SSL/TLS protocol check

       2) standard cipher categories to give you upfront an idea for the ciphers supported

       3) checks (perfect) forward secrecy: ciphers and elliptical curves

       4) server preferences (server order)

       5) server defaults (certificate info, TLS extensions, session information)

       6) HTTP header (if HTTP detected or being forced via --assume-http)

       7) vulnerabilities

       8) testing each of 370 preconfigured ciphers

       9) client simulation

OPTIONS AND PARAMETERS

       Options are either short or long options. Any long or short option requiring a value can be  called  with
       or  without an equal sign. E.g. testssl.sh -t=smtp --wide --openssl=/usr/bin/openssl <URI> (short options
       with equal sign) is equivalent to testssl.sh --starttls  smtp  --wide  --openssl  /usr/bin/openssl  <URI>
       (long  option  without  equal  sign).  Some  command  line  options can also be preset via ENV variables.
       WIDE=true OPENSSL=/usr/bin/openssl testssl.sh --starttls=smtp  <URI>  would  be  the  equivalent  to  the
       aforementioned examples. Preference has the command line over any environment variables.

       <URI> or --file <FILE> always needs to be the last parameter.

   BANNER OPTIONS
       --help (or no arg) display command line help

       -b,  --banner  displays  testssl.sh  banner,  including license, usage conditions, version of testssl.sh,
       detected openssl version, its path to it, # of ciphers of openssl, its build date and the architecture

       -v, --version same as before

       -V [pattern] , --local [pattern] pretty print all local  ciphers  supported  by  openssl  version.  If  a
       pattern  is supplied it performs a match (ignore case) on any of the strings supplied in the wide output,
       see below. The pattern will be searched in the any of the columns: hexcode, cipher suite name (OpenSSL or
       IANA),  key  exchange,  encryption, bits. It does a word pattern match for non-numbers, for number just a
       normal match applies. Numbers here are defined as [0-9,A-F].  This  means  (attention:  catch)  that  the
       pattern CBC is matched as non-word, but AES as word.

   INPUT PARAMETERS
       URI  can be a hostname, an IPv4 or IPv6 address (restriction see below) or an URL. IPv6 addresses need to
       be in square brackets. For any given parameter port 443 is assumed unless specified by appending a  colon
       and  a  port  number.  The  only preceding protocol specifier allowed is https. You need to be aware that
       checks for an IP address might not hit the vhost you  want.  DNS  resolution  (A/AAAA  record)  is  being
       performed unless you have an /etc/hosts entry for the hostname.

       --file <fname> or the equivalent -iL <fname> are mass testing options. Per default it implicitly turns on
       --warnings batch. In its first incarnation the mass testing option reads command lines from fname.  fname
       consists  of  command  lines of testssl, one line per instance. Comments after # are ignored, EOF signals
       the end of fname any subsequent lines will be ignored too. You can also supply additional  options  which
       will  be inherited to each child, e.g. When invoking testssl.sh --wide --log --file <fname> . Each single
       line in fname is parsed upon execution. If there´s a conflicting option and serial mass testing option is
       being  performed  the  check  will  be  aborted  at the time it occurs and depending on the output option
       potentially leaving you with an output file without footer. In parallel mode the mileage varies, likely a
       line won´t be scanned.

       Alternatively fname can be in nmap´s grep(p)able output format (-oG). Only open ports will be considered.
       Multiple ports per line are allowed. The ports  can  be  different  and  will  be  tested  by  testssl.sh
       according  to  common  practice  in  the  internet,  i.e.  if  nmap  shows in its output an open port 25,
       automatically -t smtp will be added before the URI whereas port 465 will be treated as  a  plain  TLS/SSL
       port,  not  requiring  an  STARTTLS  SMTP  handshake  upfront.  This  is  done by an internal table which
       correlates nmap´s open port detected to the STARTTLS/plain text decision from testssl.sh.

       Nmap´s output always returns IP addresses and only if there´s a PTR DNS record available a  hostname.  As
       it  is  not  checked by nmap whether the hostname matches the IP (A or AAAA record), testssl.sh does this
       automatically for you. If the A record of the hostname matches the IP address, the hostname is  used  and
       not  the  IP  address.  Please keep in mind that checks against an IP address might not hit the vhost you
       maybe were aiming at and thus it may lead to different results.

       A typical internal conversion to testssl.sh file format from nmap´s grep(p)able format could look like:

           10.10.12.16:443
           10.10.12.16:1443
           -t smtp host.example.com:25
           host.example.com:443
           host.example.com:631
           -t ftp 10.10.12.11:21
           10.10.12.11:8443

       Please note that fname has to be in Unix format. DOS carriage returns won´t be accepted. Instead  of  the
       command line switch the environment variable FNAME will be honored too.

       --mode  <serial|parallel>.  Mass  testing to be done serial (default) or parallel (--parallel is shortcut
       for the latter, --serial is the opposite option). Per default mass testing is being run in  serial  mode,
       i.e.  one line after the other is processed and invoked. The variable MASS_TESTING_MODE can be defined to
       be either equal serial or parallel.

       --warnings <batch|off>. The warnings parameter determines how testssl.sh will deal with situations  where
       user  input  normally  will  be  necessary.  There  are  two options. batch doesn´t wait for a confirming
       keypress when a client- or server-side probem is encountered. As of  3.0  it  just  then  terminates  the
       particular  scan. This is automatically chosen for mass testing (--file). off just skips the warning, the
       confirmation but continues the scan, independent whether it makes sense or not. Please  note  that  there
       are  conflicts  where testssl.sh will still ask for confirmation which are the ones which otherwise would
       have a drastic impact on the results. Almost any other decision will be made in  the  future  as  a  best
       guess by testssl.sh. The same can be achieved by setting the environment variable WARNINGS.

       --connect-timeout  <seconds>  This  is  useful for socket TCP connections to a node. If the node does not
       complete a TCP handshake (e.g. because it is down or behind a firewall or there´s an  IDS  or  a  tarpit)
       testssl.sh  may ususally hang for around 2 minutes or even much more. This parameter instructs testssl.sh
       to wait at most seconds for the handshake to complete before giving up. This option only works if your OS
       has a timeout binary installed. CONNECT_TIMEOUT is the corresponding enviroment variable.

       --openssl-timeout  <seconds>  This  is  especially  useful for all connects using openssl and practically
       useful for mass testing. It avoids the openssl connect to hang for ~2  minutes.  The  expected  parameter
       seconds  instructs  testssl.sh  to wait before the openssl connect will be terminated. The option is only
       available if your OS has a timeout binary installed. As there are different implementations  of  timeout:
       It  automatically  calls  the  binary  with  the  right  parameters.  OPENSSL_TIMEOUT  is  the equivalent
       environment variable.

       --basicauth <user:pass> This can be set to provide HTTP basic auth  credentials  which  are  used  during
       checks for security headers. BASICAUTH is the ENV variable you can use instead.

   SPECIAL INVOCATIONS
       -t  <protocol>,  --starttls  <protocol>  does a default run against a STARTTLS enabled protocol. protocol
       must be one of ftp, smtp, pop3, imap, xmpp, telnet, ldap, irc,  lmtp,  nntp,  postgres,  mysql.  For  the
       latter  four  you  need  e.g. the supplied OpenSSL or OpenSSL version 1.1.1. Please note: MongoDB doesn´t
       offer a STARTTLS connection, LDAP currently only works with --ssl-native. telnet and irc is WIP.

       --xmpphost <jabber_domain> is an additional option for STARTTLS  enabled  XMPP:  It  expects  the  jabber
       domain as a parameter. This is only needed if the domain is different from the URI supplied.

       --mx  <domain|host>  tests  all MX records (STARTTLS on port 25) from high to low priority, one after the
       other.

       --ip <ip> tests either the supplied IPv4 or IPv6 address instead of  resolving  host(s)  in  <URI>.  IPv6
       addresses  need  to  be  supplied  in  square  brackets. --ip=one means: just test the first A record DNS
       returns (useful for multiple IPs). If -6 and --ip=one was supplied an  AAAA  record  will  be  picked  if
       available.  The  --ip  option  might  be  also  useful  if you want to resolve the supplied hostname to a
       different  IP,  similar  as  if  you  would  edit  /etc/hosts  or  /c/Windows/System32/drivers/etc/hosts.
       --ip=proxy tries a DNS resolution via proxy.

       --proxy  <host>:<port>  does  ANY  check via the specified proxy. --proxy=auto inherits the proxy setting
       from the environment. The hostname supplied will be resolved to the first A record. In  addition  if  you
       want  lookups  via proxy you can specify DNS_VIA_PROXY=true. OCSP revocation checking (-S --phone-out) is
       not supported by OpenSSL via proxy. As supplying a proxy is an indicator for port  80  and  443  outgoing
       being blocked in your network an OCSP revocation check won´t be performed. However if IGN_OCSP_PROXY=true
       has been supplied it will be tried directly. Authentication to the proxy is not supported.  Proxying  via
       IPv6 addresses is not possible, no HTTPS or SOCKS proxy is supported.

       -6  does  (also)  IPv6  checks.  Please  note  that  testssl.sh doesn´t perform checks on an IPv6 address
       automatically, because of two reasons: testssl.sh does no connectivity checks  for  IPv6  and  it  cannot
       determine  reliably whether the OpenSSL binary you´re using has IPv6 s_client support. -6 assumes both is
       the case. If both conditions are met and you in general prefer to test for IPv6 branches as well you  can
       add  HAS_IPv6  to  your shell environment. Besides the OpenSSL binary supplied IPv6 is known to work with
       vanilla OpenSSL >= 1.1.0 and older versions >=1.0.2 in RHEL/CentOS/FC and Gentoo.

       --ssl-native Instead of using a mixture of bash sockets and a few openssl s_client  connects,  testssl.sh
       uses  the  latter  (almost)  only.  This  is  faster  at  the  moment but provides less accurate results,
       especially for the client simulation and for cipher support. For all checks you will  see  a  warning  if
       testssl.sh  cannot  tell if a particular check cannot be performed. For some checks however you might end
       up getting false negatives without a warning. This option is only recommended if you  prefer  speed  over
       accuracy  or  you  know that your target has sufficient overlap with the protocols and cipher provided by
       your openssl binary.

       --openssl <path_to_openssl> testssl.sh tries very hard to find automagically the binary  supplied  (where
       the  tree of testssl.sh resides, from the directory where testssl.sh has been started from, etc.). If all
       that doesn´t work it falls back to openssl supplied from the OS ($PATH). With this option you  can  point
       testssl.sh  to  your  binary  of  choice  and  override  any  internal  magic to find the openssl binary.
       (Environment preset via OPENSSL=<path_to_openssl>).

   TUNING OPTIONS
       --bugs does some workarounds for buggy servers like padding for old F5 devices. The option is  passed  as
       -bug  to  openssl  when  needed,  see s_client(1), environment preset via BUGS="-bugs" (1x dash). For the
       socket part testssl.sh has always workarounds in place to cope with broken server implementations.

       --assuming-http testssl.sh normally does upfront an application protocol detection. In cases  where  HTTP
       cannot be automatically detected you may want to use this option. It enforces testssl.sh not to skip HTTP
       specific tests (HTTP header) and to run a browser based client simulation.  Please  note  that  sometimes
       also the severity depends on the application protocol, e.g. SHA1 signed certificates, the lack of any SAN
       matches and some vulnerabilities will be punished harder when checking a web server as opposed to a  mail
       server.

       -n,  --nodns <min|none> tells testssl.sh which DNS lookups should be performed. min uses only forward DNS
       resolution (A and AAAA record or MX record) and skips CAA lookups and PTR records  from  the  IP  address
       back  to a DNS name. none performs no DNS lookups at all. For the latter you either have to supply the IP
       address as a target, to use --ip or have the IP address in /etc/hosts. The use  of  the  switch  is  only
       useful  if  you either can´t or are not willing to perform DNS lookups. The latter can apply e.g. to some
       pentests. In general this option could e.g. help you to avoid timeouts  by  DNS  lookups.  NODNS  is  the
       enviroment variable for this.

       --sneaky  For  HTTP header checks testssl.sh uses normally the server friendly HTTP user agent TLS tester
       from ${URL}. With this option your traces are less verbose and a Firefox user agent  is  being  used.  Be
       aware  that  it  doesn´t  hide  your  activities.  That  is  just  not  possible  (environment preset via
       SNEAKY=true).

       --ids-friendly is a switch which may help to get a scan finished which otherwise would be  blocked  by  a
       server  side  IDS.  This switch skips tests for the following vulnerabilities: Heartbleed, CCS Injection,
       Ticketbleed and ROBOT. The environment variable OFFENSIVE set to false  will  achieve  the  same  result.
       Please be advised that as an alternative or as a general approach you can try to apply evasion techniques
       by changing the variables USLEEP_SND and / or USLEEP_REC and maybe MAX_WAITSOCK.

       --phone-out Checking for revoked certificates via CRL and OCSP is  not  done  per  default.  This  switch
       instructs testssl.sh to query external -- in a sense of the current run -- URIs. By using this switch you
       acknowledge that the check might have privacy issues, a download of  several  megabytes  (CRL  file)  may
       happen  and  there  may  be  network connectivity problems while contacting the endpoint which testssl.sh
       doesn´t handle. PHONE_OUT is the environment variable for this which needs to be set to true if you  want
       this.

       --add-ca  <cafile>  enables you to add your own CA(s) for trust chain checks. cafile can be a single path
       or multiple paths as a comma separated list of root CA  files.  Internally  they  will  be  added  during
       runtime  to  all  CA  stores.  This  is  (only) useful for internal hosts whose certificates is issued by
       internal CAs. Alternatively ADDITIONAL_CA_FILES is the environment variable for this.

   SINGLE CHECK OPTIONS
       Any single check switch supplied as an argument prevents testssl.sh from doing a  default  run.  It  just
       takes  this  and  if  supplied  other  options and runs them - in the order they would also appear in the
       default run.

       -e, --each-cipher checks each of the (currently configured) 370 ciphers via openssl + sockets remotely on
       the  server  and reports back the result in wide mode. If you want to display each cipher tested you need
       to add --show-each. Per default it lists the following parameters: hexcode, OpenSSL  cipher  suite  name,
       key  exchange,  encryption  bits, IANA/RFC cipher suite name. Please note the --mapping parameter changes
       what cipher suite names you will see here and at which position. Also please note that the bit length for
       the  encryption  is shown and not the security length, albeit it´ll be sorted by the latter. For 3DES due
       to the Meet-in-the-Middle problem the bit size of 168 bits is equivalent to  the  security  size  of  112
       bits.

       -E, --cipher-per-proto is similar to -e, --each-cipher. It checks each of the possible ciphers, here: per
       protocol. If you want to display each cipher tested you need to add --show-each. The output is sorted  by
       security strength, it lists the encryption bits though.

       -s,  --std, --standard tests certain lists of cipher suites by strength. Those lists are (openssl ciphers
       $LIST, $LIST from below:)

       •   NULL encryption ciphers: ´NULL:eNULL´

       •   Anonymous NULL ciphers: ´aNULL:ADH´

       •   Export ciphers (w/o the preceding ones): ´EXPORT:!ADH:!NULL´

       •   LOW (64 Bit + DES ciphers, without EXPORT ciphers): ´LOW:DES:RC2:RC4:!ADH:!EXP:!NULL:!eNULL´

       •   3DES + IDEA Ciphers: ´3DES:IDEA:!aNULL:!ADH´

       •   Average                                        grade                                         Ciphers:
           ´HIGH:MEDIUM:AES:CAMELLIA:ARIA:!IDEA:!CHACHA20:!3DES:!RC2:!RC4:!AESCCM8:!AESCCM:!AESGCM:!ARIAGCM:!aNULL´

       •   Strong grade Ciphers (AEAD): ´AESGCM:CHACHA20:AESGCM:CamelliaGCM:AESCCM8:AESCCM´

       -f, --pfs, --fs,--nsa Checks robust (perfect) forward secrecy key exchange. "Robust" means  that  ciphers
       having  intrinsic  severe  weaknesses  like  Null  Authentication  or  Encryption,  3DES and RC4 won´t be
       considered here. There shouldn´t be the wrong impression that a secure key exchange has been taking place
       and  everything  is  fine  when  in  reality  the encryption sucks. Also this section lists the available
       elliptical curves and Diffie Hellman groups, as well as FFDHE groups (TLS 1.2 and TLS 1.3).

       -p, --protocols checks TLS/SSL protocols SSLv2, SSLv3, TLS 1.0 through TLS 1.3 and for HTTP:  SPDY  (NPN)
       and ALPN, a.k.a. HTTP/2. For TLS 1.3 several drafts (from 18 on) and final are supported and being tested
       for.

       -P, --preference displays the servers preferences: cipher order, with  used  openssl  client:  negotiated
       protocol  and  cipher.  If there´s a cipher order enforced by the server it displays it for each protocol
       (openssl+sockets). If there´s not, it displays instead which ciphers from the  server  were  picked  with
       each protocol.

       -S, --server_defaults displays information from the server hello(s):

       •   Available TLS extensions,

       •   TLS ticket + session ID information/capabilities,

       •   session resumption capabilities,

       •   Time skew relative to localhost (most server implementations return random values).

       •   Several certificate information

           •   signature algorithm,

           •   key size,

           •   key usage and extended key usage,

           •   fingerprints and serial

           •   Common Name (CN), Subject Alternative Name (SAN), Issuer,

           •   Trust via hostname + chain of trust against supplied certificates

           •   EV certificate detection

           •   experimental "eTLS" detection

           •   validity: start + end time, how many days to go (warning for certificate lifetime >=5 years)

           •   revocation  info  (CRL,  OCSP,  OCSP stapling + must staple). When --phone-out supplied it checks
               against the certificate issuer whether the host certificate has been revoked (plain OCSP, CRL).

           •   displaying DNS Certification Authority Authorization resource record

           •   Certificate Transparency info (if provided by server).

       For the trust chain check 5 certificate stores are provided. If the test against one of the trust  stores
       failed,  the  one  is being identified and the reason for the failure is displayed - in addition the ones
       which succeeded are displayed too. You can configure your own CA  via  ADDITIONAL_CA_FILES,  see  section
       FILES  below.  If  the server provides no matching record in Subject Alternative Name (SAN) but in Common
       Name (CN), it will be indicated as this is deprecated. Also for multiple server  certificates  are  being
       checked  for  as  well as for the certificate reply to a non-SNI (Server Name Indication) client hello to
       the IP address. Regarding the TLS clock skew: it displays the time difference to the client. Only  a  few
       TLS  stacks  nowadays  still  support  this and return the local clock gmt_unix_time, e.g. IIS, openssl <
       1.0.1f. In addition to the HTTP date you could e.g. derive that there are different hosts where your  TLS
       and your HTTP request ended -- if the time deltas differ significantly.

       -x  <pattern>,  --single-cipher <pattern> tests matched pattern of ciphers against a server. Patterns are
       similar to -V pattern , --local pattern, see above about matching.

       -h, --header, --headers if the service is HTTP (either by detection or by enforcing via --assume-http. It
       tests several HTTP headers like

       •   HTTP Strict Transport Security (HSTS)

       •   HTTP Public Key Pinning (HPKP)

       •   Server banner

       •   HTTP date+time

       •   Server banner like Linux or other Unix vendor headers

       •   Application banner (PHP, RoR, OWA, SharePoint, Wordpress, etc)

       •   Reverse proxy headers

       •   Web server modules

       •   IPv4 address in header

       •   Cookie (including Secure/HTTPOnly flags)

       •   Decodes BIG IP F5 non-encrypted cookies

       •   Security  headers  (X-Frame-Options,  X-XSS-Protection, Expect-CT,... , CSP headers). Nonsense is not
           yet detected here.

       --c, --client-simulation This simulates a handshake with a number of standard clients  so  that  you  can
       figure  out which client cannot or can connect to your site. For the latter case the protocol, cipher and
       curve is displayed, also if there´s Forward Secrecy. testssl.sh uses a handselected set of clients  which
       are  retrieved by the SSLlabs API. The output is aligned in columns when combined with the --wide option.
       If you want the full nine yards of clients displayed use the environment variable ALL_CLIENTS.

       -g, --grease checks several server implementation bugs like tolerance to size limitations and GREASE, see
       https://www.ietf.org/archive/id/draft-ietf-tls-grease-01.txt . This checks doesn´t run per default.

   VULNERABILITIES
       -U,  --vulnerable,  --vulnerabilities  Just tests all (of the following) vulnerabilities. The environment
       variable VULN_THRESHLD determines after which value a separate headline for each vulnerability  is  being
       displayed.  Default  is 1 which means if you check for two vulnerabilities, only the general headline for
       vulnerabilities section is displayed -- in addition to the vulnerability and the result.  Otherwise  each
       vulnerability or vulnerability section gets its own headline in addition to the output of the name of the
       vulnerabilty and test result. A vulnerability section is comprised of  more  than  one  check,  e.g.  the
       renegotiation vulnerability check has two checks, so has Logjam.

       -H,  --heartbleed  Checks  for  Heartbleed,  a  memory leakage in openssl. Unless the server side doesn´t
       support the heartbeat extension it is likely that this check runs into a timeout. The seconds to wait for
       a reply can be adjusted with HEARTBLEED_MAX_WAITSOCK. 8 is the default.

       -I,  --ccs,  --ccs-injection  Checks  for CCS Injection which is an openssl vulnerability. Sometimes also
       here the check needs to wait for a reply. The predefined timeout of 5 seconds can  be  changed  with  the
       environment variable CCS_MAX_WAITSOCK.

       -T, --ticketbleed Checks for Ticketbleed memory leakage in BigIP loadbalancers.

       -BB, --robot Checks for vulnerability to ROBOT / (Return Of Bleichenbacher´s Oracle Threat) attack.

       -R,   --renegotiation   Tests  renegotiation  vulnerabilities.  Currently  there´s  a  check  for  Secure
       Renegotiation and for Secure Client-Initiated Renegotiation. Please be aware that vulnerable  servers  to
       the latter can likely be DoSed very easily (HTTP). A check for Insecure Client-Initiated Renegotiation is
       not yet implemented.

       -C, --compression, --crime Checks for CRIME (Compression Ratio Info-leak Made Easy) vulnerability in TLS.
       CRIME in SPDY is not yet being checked for.

       -B,  --breach  Checks  for  BREACH  (Browser  Reconnaissance and Exfiltration via Adaptive Compression of
       Hypertext) vulnerability. As for this vulnerability HTTP level compression is a prerequisite it´ll be not
       tested  if  HTTP cannot be detected or the detection is not enforced via `--assume-http. Please note that
       only the URL supplied (normally "/" ) is being tested.

       -O, --poodle Tests for SSL POODLE (Padding Oracle On  Downgraded  Legacy  Encryption)  vulnerability.  It
       basically checks for the existence of CBC ciphers in SSLv3.

       -Z,  --tls-fallback  Checks  TLS_FALLBACK_SCSV  mitigation.  TLS_FALLBACK_SCSV is basically a ciphersuite
       appended to the Client Hello trying to prevent protocol downgrade attacks by a Man in the Middle.

       -W, --sweet32 Checks for vulnerability to SWEET32 by testing 64 bit block ciphers (3DES, RC2 and IDEA).

       -F, --freak Checks for FREAK vulnerability (Factoring RSA Export Keys) by testing for EXPORT RSA ciphers

       -D, --drown Checks for DROWN vulnerability (Decrypting RSA with  Obsolete  and  Weakened  eNcryption)  by
       checking  whether the SSL 2 protocol is available at the target. Please note that if you use the same RSA
       certificate elsewhere you might be vulnerable too. testssl.sh doesn´t  check  for  this  but  provides  a
       helpful link @ censys.io which provides this service.

       -J,  --logjam  Checks  for  LOGJAM  vulnerability  by  checking for DH EXPORT ciphers. It also checks for
       "common primes" which are preconfigured DH keys. DH keys =< 1024 Bit will be penalized. Also FFDHE groups
       (TLS 1.2) will be displayed here.

       -A, --beast Checks BEAST vulnerabilities in SSL 3 and TLS 1.0 by testing the usage of CBC ciphers.

       -L, --lucky13 Checks for LUCKY13 vulnerability. It checks for the presence of CBC ciphers in TLS versions
       1.0 - 1.2.

       -4, --rc4, --appelbaum Checks which RC4 stream ciphers are being offered.

   OUTPUT OPTIONS
       -q, --quiet Normally testssl.sh displays a banner on  stdout  with  several  version  information,  usage
       rights and a warning. This option suppresses it. Please note that by choosing this option you acknowledge
       usage terms and the warning normally appearing in the banner.

       --wide Except the "each cipher output" all tests displays the single cipher name (scheme see below). This
       option  enables testssl.sh to display also for the following sections the same output as for testing each
       ciphers: BEAST, PFS, RC4. The client simulation has also a wide mode. The difference here  is  restricted
       to a column aligned output and a proper headline. The environment variable WIDE can be used instead.

       --mapping <openssl|iana|no-openssl|no-iana>openssl: use the OpenSSL cipher suite name as the primary name cipher suite name form (default),

       •   iana: use the IANA cipher suite name as the primary name cipher suite name form.

       •   no-openssl: don´t display the OpenSSL cipher suite name, display IANA names only.

       •   no-iana: don´t display the IANA cipher suite name, display OpenSSL names only.

       Please  note  that  in testssl.sh 3,0 you can still use rfc instead of iana and no-rfc instead of no-iana
       but it´ll disappear after 3.0.

       --show-each This is an option for all wide modes only:  it  displays  all  ciphers  tested  --  not  only
       succeeded ones. SHOW_EACH_C is your friend if you prefer to set this via the shell environment.

       --color  <0|1|2|3>  determines  the use of colors on the screen and in the log file: 2 is the default and
       makes use of ANSI and termcap escape codes on your terminal. 1 just uses non-colored mark-up  like  bold,
       italics, underline, reverse. 0 means no mark-up at all = no escape codes. This is also what you want when
       you want a log file without any escape codes. 3 will color ciphers and EC according to an  internal  (not
       yet perfect) rating. Setting the environment variable COLOR to the value achieves the same result. Please
       not that OpenBSD and early FreeBSD do not support italics.

       --colorblind Swaps green and blue colors in the output, so that this percentage of folks  (up  to  8%  of
       males,   see   https://en.wikipedia.org/wiki/Color_blindness)  can  distinguish  those  findings  better.
       COLORBLIND is the according variable if you want to set this in the environment.

       --debug <0-6> This gives you additional output on the screen (2-6), only useful for debugging.  DEBUG  is
       the according environment variable which you can use. There are six levels (0 is the default, thus it has
       no effect):

       1.  screen output normal but leaves useful debug output in /tmp/testssl.XXXXXX/  .  The  info  about  the
           exact directory is included in the screen output in the end of the run.

       2.  lists more what´s going on, status (high level) and connection errors, a few general debug output

       3.  even slightly more info: hexdumps + other info

       4.  display bytes sent via sockets

       5.  display bytes received via sockets

       6.  whole 9 yards

   FILE OUTPUT OPTIONS
       --log, --logging Logs stdout also to ${NODE}-p${port}${YYYYMMDD-HHMM}.log in current working directory of
       the shell. Depending on the color output option (see above) the output file will contain color and  other
       markup  escape  codes,  unless  you specify --color 0 too. cat and -- if properly configured less -- will
       show the output properly formatted on your terminal. The output shows a banner with the almost  the  same
       information  as  on  the screen. In addition it shows the command line of the testssl.sh instance. Please
       note that the resulting log file is formatted according  to  the  width  of  your  screen  while  running
       testssl.sh. You can override the width with the environment variable TERM_WIDTH.

       --logfile  <logfile>  or -oL <logfile> Instead of the previous option you may want to use this one if you
       want to log into a directory or if you rather want to specify the log file name yourself. If logfile is a
       directory  the output will put into logfile/${NODE}-p${port}${YYYYMMDD-HHMM}.log. If logfile is a file it
       will use that file name, an absolute path is also permitted here. LOGFILE is the variable you need to set
       if you prefer to work environment variables instead. Please note that the resulting log file is formatted
       according to the width of your screen while running testssl.sh. You  can  override  the  width  with  the
       environment variable TERM_WIDTH.

       --json  Logs  additionally  to  JSON  file  ${NODE}-p${port}${YYYYMMDD-HHMM}.json  in the current working
       directory of the shell. The resulting JSON file is opposed to --json-pretty  flat  --  which  means  each
       section is self contained and has an identifier for each single check, the hostname/IP address, the port,
       severity and the finding. For vulnerabilities it may contain a CVE and CWE entry too. The output  doesn´t
       contain a banner or a footer.

       --jsonfile  <jsonfile>  or  -oj <jsonfile> Instead of the previous option you may want to use this one if
       you want to log the JSON out put into a directory or if you rather want to  specify  the  log  file  name
       yourself.      If      jsonfile      is      a     directory     the     output     will     put     into
       logfile/${NODE}-p${port}${YYYYMMDD-HHMM}.json. Ifjsonfile` is a file it  will  use  that  file  name,  an
       absolute path is also permitted here.

       --json-pretty Logs additionally to JSON file ${NODE}-p${port}${YYYYMMDD-HHMM}.json in the current working
       directory of the shell. The resulting JSON file is opposed  to--json`  non-flat  --  which  means  it  is
       structured.  The  structure  contains a header similar to the banner on the screen, including the command
       line, scan host, openssl binary used, testssl version and epoch of the start time. Then  for  every  test
       section  of  testssl.sh  it  contains  a  separate JSON object/section. Each finding has a key/value pair
       identifier with the identifier for each single check, the severity and the finding.  For  vulnerabilities
       it may contain a CVE and CWE entry too. The footer lists the scan time in seconds.

       --jsonfile-pretty  <jsonfile>  or -oJ <jsonfile> Similar to the aforementioned --jsonfile or --logfile it
       logs the output in pretty JSON format (see --json-pretty)  into  a  file  or  a  directory.  For  further
       explanation see --jsonfile or --logfile.

       --csv  Logs  additionally  to  a  CSV  file  ${NODE}-p${port}${YYYYMMDD-HHMM}.csv  in the current working
       directory of the shell. The output contains a header with the keys, the values are the  same  as  in  the
       flat  JSON  format  (identifier  for  each single check, the hostname/IP address, the port, severity, the
       finding and for vulnerabilities a CVE and CWE number).

       --csvfile <csvfile> or -oC <csvfile> Similar to the aforementioned --jsonfile or --logfile  it  logs  the
       output  in  CSV  format  (see --cvs) additionally into a file or a directory. For further explanation see
       --jsonfile or --logfile.

       --html Logs additionally to an HTML file ${NODE}-p${port}${YYYYMMDD-HHMM}.html  in  the  current  working
       directory  of  the  shell.  It  contains  a  1:1  output  of  the console. In former versions there was a
       non-native option to use "aha" (Ansi HTML Adapter: github.com/theZiz/aha) like testssl.sh [options] <URI>
       | aha >output.html. This is not necessary anymore.

       --htmlfile <htmlfile> or -oH <htmlfile> Similar to the aforementioned --jsonfile or --logfile it logs the
       output in HTML format (see --html) additionally into a file or a directory. For further  explanation  see
       --jsonfile or --logfile.

       -oA  <filename>  /  --outFile  <filename>  Similar  to  nmap  it does a file output to all available file
       formats: LOG, JSON  pretty,  CSV,  HTML.  If  the  filename  supplied  is  equal  auto  the  filename  is
       automatically  generated using ´${NODE}-p${port}${YYYYMMDD-HHMM}.${EXT}´ with the according extension. If
       a      directory      is      provided       all       output       files       will       put       into
       <filename>/${NODE}-p${port}${YYYYMMDD-HHMM}.{log,json,csv,html}.

       -oa <filename> / --outfile <filename> Does the same as the previous option but uses flat JSON instead.

       --hints  This  option  is  not  in use yet. This option is meant to give hints how to fix a finding or at
       least a help to improve something. GIVE_HINTS is the environment variable for this.

       --severity <severity> For CSV and both JSON outputs this will only add findings to the output file  if  a
       severity  is  equal  or higher than the severity value specified. Allowed are <LOW|MEDIUM|HIGH|CRITICAL>.
       WARN is another level which translates to a client-side scanning error or problem. Thus you  will  always
       see them in a file if they occur.

       --append  Normally, if an output file already exists and it has a file size greater zero, testssl.sh will
       prompt you to manually remove the file exit with an error. --append however will  append  to  this  file,
       without a header. The environment variable APPEND does the same. Be careful using this switch/variable. A
       complementary option which overwrites an existing file doesn´t exist per design.

       --outprefix <fname_prefix> Prepend output filename prefix fname_prefix before ´${NODE}-´. You can use  as
       well   the   environment   variable   FNAME_PREFIX.   Using   this   any   output  files  will  be  named
       <fname_prefix>-${NODE}-p${port}${YYYYMMDD-HHMM}.<format> when no  file  name  of  the  respective  output
       option was specified. If you do not like the separator ´-´ you can as well supply a <fname_prefix> ending
       in ´.´, ´_´ or ´,´. In this case or if you already supplied ´-´ no additional ´-´  will  be  appended  to
       <fname_prefix>.

       A few file output options can also be preset via environment variables.

   COLOR RATINGS
       Testssl.sh makes use of (the eight) standard terminal colors. The color scheme is as follows:

       •   light red: a critical finding

       •   red: a high finding

       •   brown: a medium finding

       •   yellow: a low finding

       •   green  (blue  if  COLORBLIND is set): something which is either in general a good thing or a negative
           result of a check which otherwise results in a high finding

       •   light green (light blue if COLORBLIND is set) : something which is either  in  general  a  very  good
           thing or a negative result of a check which otherwise results in a critical finding

       •   no color at places where also a finding can be expected: a finding on an info level

       •   cyan: currently only used for --show-each or an additional hint

       •   magenta:  signals a warning condition, e.g. either a local lack of capabilities on the client side or
           another problem

       •   light magenta: a fatal error which either requires strict consent from the  user  to  continue  or  a
           condition which leaves no other choice for testssl.sh to quit

       What  is  labeled  as  "light"  above  appears  as such on the screen but is technically speaking "bold".
       Besides --color=3 will color ciphers according to an internal and rough rating.

       Markup (without any color) is used in the following manner:

       •   bold: for the name of the test

       •   underline + bold: for the headline of each test section

       •   underline: for a sub-headline

       •   italics: for strings just reflecting a value read from the server

   TUNING via ENV variables and more options
       Except the environment variables mentioned above which can replace command line options here a some which
       cannot  be set otherwise. Variables used for tuning are preset with reasonable values. There should be no
       reason to change them unless you use testssl.sh under special conditions.

       •   TERM_WIDTH is a variable which overrides  the  auto-determined  terminal  width  size.  Setting  this
           variable  normally only makes sense if you log the output to a file using the --log, --logfile or -oL
           option.

       •   DEBUG_ALLINONE / SETX: when setting one of those to true testssl.sh falls back to the  standard  bash
           behavior,  i.e.  calling  bash -x testssl.sh it displays the bash debugging output not in an external
           file /tmp/testssl-<XX>.log

       •   DEBUGTIME: Profiling option. When using bash´s debug mode and when this is set to true, it  generates
           a  separate  text  file  with  epoch times in /tmp/testssl-<XX>.time. They need to be concatenated by
           paste /tmp/testssl-<XX>.{time,log}

       •   EXPERIMENTAL=true is an option which is sometimes used in the development  process  to  make  testing
           easier. In released versions this has no effect.

       •   ALL_CLIENTS=true runs a client simulation with all (currently 126) clients when testing HTTP.

       •   UNBRACKTD_IPV6:  needs  to  be  set to true for some old versions of OpenSSL (like from Gentoo) which
           don´t support [bracketed] IPv6 addresses

       •   NO_ENGINE: if you have problems with garbled output containing the word ´engine´ you  might  want  to
           set  this  to  true. It forces testssl.sh not try to configure openssl´s engine or a non existing one
           from libressl

       •   HEADER_MAXSLEEP: To wait how long before killing the process to retrieve  a  service  banner  /  HTTP
           header

       •   MAX_WAITSOCK:  It  instructs  testssl.sh  to  wait until the specified time before declaring a socket
           connection dead. Don´t change this unless you´re absolutely sure  what  you´re  doing.  Value  is  in
           seconds.

       •   CCS_MAX_WAITSOCK  Is the similar to above but applies only to the CCS handshakes, for both of the two
           the two CCS payload. Don´t change this unless you´re absolutely sure what you´re doing. Value  is  in
           seconds.

       •   HEARTBLEED_MAX_WAITSOCK  Is  the  similar  to  MAX_WAITSOCK but applies only to the ServerHello after
           sending the Heartbleed payload. Don´t change this unless you´re absolutely sure  what  you´re  doing.
           Value is in seconds.

       •   MEASURE_TIME_FILE For seldom cases when you don´t want the scan time to be included in the output you
           can set this to false.

       •   STARTTLS_SLEEP is per default set to 10 (seconds). That´s the value testssl.sh waits for a string  in
           the STARTTLS handshake before giving up.

       •   MAX_PARALLEL  is  the  maximum  number of tests to run in parallel in parallel mass testing mode. The
           default value of 20 may be made larger on systems with faster processors.

       •   MAX_WAIT_TEST is the maximum time (in seconds) to wait for a single test  in  parallel  mass  testing
           mode to complete. The default is 1200.

       •   HSTS_MIN  is  preset  to  179  (days). If you want warnings sooner or later for HTTP Strict Transport
           Security you can change this.

       •   HPKP_MIN is preset to 30 (days). If you want warnings sooner or later for HTTP Public Key Pinning you
           can change this

       •   DAYS2WARN1  is  the  first  threshold  when  you´ll be warning of a certificate expiration of a host,
           preset to 60 (days). For Let´s Encrypt this value will be divided internally by 2.

       •   DAYS2WARN2 is the second threshold when you´ll be warning of a  certificate  expiration  of  a  host,
           preset to 30 (days). For Let´s Encrypt this value will be divided internally by 2.

       •   TESTSSL_INSTALL_DIR  is  the derived installation directory of testssl.sh. Relatively to that the bin
           and mandatory etc directory will be looked for.

       •   CA_BUNDLES_PATH: If you have an own set of CA bundles or you want to point testssl.sh to  a  specific
           location  of  a  CA bundle, you can use this variable to set the directory which testssl.sh will use.
           Please note that it overrides completely the builtin path of testssl.sh which  means  that  you  will
           only test against the bundles you point to. Also you might want to use ~/utils/create_ca_hashes.sh to
           create the hashes for HPKP.

       •   MAX_SOCKET_FAIL: A number which tells testssl.sh how often a TCP socket connection  may  fail  before
           the  program  gives up and terminates. The default is 2. You can increase it to a higher value if you
           frequently see a message like Fatal error: repeated openssl s_client connect  problem,  doesn´t  make
           sense to continue.

       •   MAX_OSSL_FAIL:  A number which tells testssl.sh how often an OpenSSL s_client connect may fail before
           the program gives up and terminates. The default is 2. You can increase it to a higher value  if  you
           frequently see a message like Fatal error: repeated TCP connect problems, giving up.

       •   MAX_HEADER_FAIL: A number which tells testssl.sh how often a HTTP GET request over OpenSSL may return
           an empty file before the program gives up and terminates.  The  default  is  3.  Also  here  you  can
           incerase  the  threshold  when  you  spot  messages  like  Fatal  error: repeated HTTP header connect
           problems, doesn´t make sense to continue.

EXAMPLES

         testssl.sh testssl.sh

       does a default run on https://testssl.sh (protocols, standard  cipher  lists,  PFS,  server  preferences,
       server defaults, vulnerabilities, testing all known 370 ciphers, client simulation.

             testssl.sh testssl.net:443

       does  the  same  default run as above with the subtle difference that testssl.net has two IPv4 addresses.
       Both are tested.

             testssl.sh --ip=one --wide https://testssl.net:443

       does the same checks as above, with the  difference  that  one  IP  address  is  being  picked  randomly.
       Displayed is everything where possible in wide format.

             testssl.sh -6 https://testssl.net

       As opposed to the first example it also tests the IPv6 part -- supposed you have an IPv6 network and your
       openssl supports IPv6 (see above).

             testssl.sh -t smtp smtp.gmail.com:25

       Checks are done via a STARTTLS handshake on the plain text port 25. It checks every IP on smtp.gmail.com.

               testssl.sh --starttls=imap imap.gmx.net:143

       does the same on the plain text IMAP port.

       Please note that for plain TLS-encrypted ports you must not specify the protocol option when no  STARTTLS
       handshake  is  offered:  testssl.sh  smtp.gmail.com:465  just  checks  the  encryption on the SMTPS port,
       testssl.sh imap.gmx.net:993 on the IMAPS port. Also MongoDB which provides TLS support  without  STARTTLS
       can be tested directly.

RFCs and other standards

       •   RFC 2246: The TLS Protocol Version 1.0

       •   RFC 2818: HTTP Over TLS

       •   RFC 2595: Using TLS with IMAP, POP3 and ACAP

       •   RFC 3207: SMTP Service Extension for Secure SMTP over Transport Layer Security

       •   RFC 3501: INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1

       •   RFC 4346: The Transport Layer Security (TLS) Protocol Version 1.1

       •   RFC 4366: Transport Layer Security (TLS) Extensions

       •   RFC 4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)

       •   RFC 5077: Transport Layer Security (TLS) Session Resumption

       •   RFC 5246: The Transport Layer Security (TLS) Protocol Version 1.2

       •   RFC  5280: Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL)
           Profile

       •   RFC 5321: Simple Mail Transfer Protocol

       •   RFC 5746: Transport Layer Security (TLS) Renegotiation Indication Extension

       •   RFC 6066: Transport Layer Security (TLS) Extensions: Extension Definitions

       •   RFC 6101: The Secure Sockets Layer (SSL) Protocol Version 3.0

       •   RFC 6120: Extensible Messaging and Presence Protocol (XMPP): Core

       •   RFC 6125: Domain-Based Application Service Identity [..]

       •   RFC 6797: HTTP Strict Transport Security (HSTS)

       •   RFC 6961: The Transport Layer Security (TLS) Multiple Certificate Status Request Extension

       •   RFC 7469: Public Key Pinning Extension for HTTP (HPKP)

       •   RFC 7507: TLS Fallback Signaling Cipher Suite Value (SCSV) for Preventing Protocol Downgrade Attacks

       •   RFC 7627: Transport Layer Security (TLS) Session Hash and Extended Master Secret Extension

       •   RFC 7633: X.509v3 Transport Layer Security (TLS) Feature Extension

       •   RFC 7465: Prohibiting RC4 Cipher Suites

       •   RFC 7685: A Transport Layer Security (TLS) ClientHello Padding Extension

       •   RFC 7905: ChaCha20-Poly1305 Cipher Suites for Transport Layer Security (TLS)

       •   RFC 7919: Negotiated Finite Field Diffie-Hellman Ephemeral Parameters for Transport Layer Security

       •   RFC 8143: Using Transport Layer Security (TLS) with Network News Transfer Protocol (NNTP)

       •   RFC 8446: The Transport Layer Security (TLS) Protocol Version 1.3

       •   W3C CSP: Content Security Policy Level 1-3

       •   TLSWG Draft: The Transport Layer Security (TLS) Protocol Version 1.3

EXIT STATUS

       •   0 testssl.sh finished successfully without errors and without ambiguous results

       •   1 testssl.sh has encountered exactly one ambiguous situation or an error during run

       •   1+n same as previous. The errors or ambiguous results are added, also per IP.

       •   50-200 reserved for returning a vulnerability scoring for system monitoring or a CI tools

       •   242 (ERR_CHILD) Child received a signal from master

       •   244 (ERR_RESOURCE) Resources testssl.sh needs couldn´t be read

       •   245 (ERR_CLUELESS) Weird state, either though user options or testssl.sh

       •   246 (ERR_CONNECT) Connectivity problem

       •   247 (ERR_DNSLOOKUP) Problem with resolving IP addresses or names

       •   248 (ERR_OTHERCLIENT) Other client problem

       •   249 (ERR_DNSBIN) Problem with DNS lookup binaries

       •   250 (ERR_OSSLBIN) Problem with OpenSSL binary

       •   251 (ERR_NOSUPPORT) Feature requested is not supported

       •   252 (ERR_FNAMEPARSE) Input file couldn´t be parsed

       •   253 (ERR_FCREATE) Output file couldn´t be created

       •   254 (ERR_CMDLINE) Cmd line couldn´t be parsed

       •   255 (ERR_BASH) Bash version incorrect

FILES

       etc/*pem are the certificate stores from Apple, Linux, Mozilla Firefox, Windows and Java.

       etc/client-simulation.txt contains client simulation data.

       etc/cipher-mapping.txt provides a mandatory file with mapping from OpenSSL cipher  suites  names  to  the
       ones from IANA / used in the RFCs.

       etc/tls_data.txt provides a mandatory file for ciphers (bash sockets) and key material.

AUTHORS

       Developed by Dirk Wetter, David Cooper and many others, see CREDITS.md .

       Copyright  ©  2012  Dirk Wetter. License GPLv2: Free Software Foundation, Inc. This is free software: you
       are free to change and redistribute it under the terms of the license. Usage WITHOUT ANY WARRANTY. USE at
       your OWN RISK!

       If  you´re  offering  testssl.sh as a public and / or paid service in the internet you need to mention to
       your audience that you´re using this program and where to get this program from.

LIMITATION

       All native Windows platforms emulating Linux are known to be slow.

BUGS

       Probably. Current known ones and interface for filing new ones: https://testssl.sh/bugs/ .

SEE ALSO

       ciphers(1), openssl(1), s_client(1), x509(1),  verify(1),  ocsp(1),  crl(1),  bash(1)  and  the  websites
       https://testssl.sh/ and https://github.com/drwetter/testssl.sh/ .

                                                  January 2020                                        TESTSSL(1)