3

I have a server which I want to check if it supports sslv2.

from a remote machine I do the following:

 openssl s_client -ssl2 -connect something.somethingcool.com:443

But this returns:

unknown option -ssl2
usage: s_client args

 -host host     - use -connect instead
 -port port     - use -connect instead
 -connect host:port - who to connect to (default is localhost:4433)
 -verify arg   - turn on peer certificate verification
 -cert arg     - certificate file to use, PEM format assumed
 -certform arg - certificate format (PEM or DER) PEM default
 -key arg      - Private key file to use, in cert file if
                 not specified but cert file is.
 -keyform arg  - key format (PEM or DER) PEM default
 -pass arg     - private key file pass phrase source
 -CApath arg   - PEM format directory of CA's
 -CAfile arg   - PEM format file of CA's
 -reconnect    - Drop and re-make the connection with the same Session-ID
 -pause        - sleep(1) after each read(2) and write(2) system call
 -showcerts    - show all certificates in the chain
 -debug        - extra output
 -msg          - Show protocol messages
 -nbio_test    - more ssl protocol testing
 -state        - print the 'ssl' states
 -nbio         - Run with non-blocking IO
 -crlf         - convert LF from terminal into CRLF
 -quiet        - no s_client output
 -ign_eof      - ignore input eof (default when -quiet)
 -no_ign_eof   - don't ignore input eof
 -psk_identity arg - PSK identity
 -psk arg      - PSK in hex (without 0x)
 -srpuser user     - SRP authentification for 'user'
 -srppass arg      - password for 'user'
 -srp_lateuser     - SRP username into second ClientHello message
 -srp_moregroups   - Tolerate other than the known g N values.
 -srp_strength int - minimal mength in bits for N (default 1024).
 -ssl2         - just use SSLv2
 -ssl3         - just use SSLv3
 -tls1_2       - just use TLSv1.2
 -tls1_1       - just use TLSv1.1
 -tls1         - just use TLSv1
 -dtls1        - just use DTLSv1
 -fallback_scsv - send TLS_FALLBACK_SCSV
 -mtu          - set the link layer MTU
 -no_tls1_2/-no_tls1_1/-no_tls1/-no_ssl3/-no_ssl2 - turn off that protocol
 -bugs         - Switch on all SSL implementation bug workarounds
 -serverpref   - Use server's cipher preferences (only SSLv2)
 -cipher       - preferred cipher to use, use the 'openssl ciphers'
                 command to see what is available
 -starttls prot - use the STARTTLS command before starting TLS
                 for those protocols that support it, where
                 'prot' defines which one to assume.  Currently,
                 only "smtp", "pop3", "imap", "ftp" and "xmpp"
                 are supported.
 -engine id    - Initialise and use the specified engine
 -rand file:file:...
 -sess_out arg - file to write SSL session to
 -sess_in arg  - file to read SSL session from
 -servername host  - Set TLS extension servername in ClientHello
 -tlsextdebug      - hex dump of all TLS extensions received
 -status           - request certificate status from server
 -no_ticket        - disable use of RFC4507bis session tickets
 -nextprotoneg arg - enable NPN extension, considering named protocols supported (comma-separated list)
 -legacy_renegotiation - enable use of legacy renegotiation (dangerous)
 -use_srtp profiles - Offer SRTP key management with a colon-separated profile list
 -keymatexport label   - Export keying material using label
 -keymatexportlen len  - Export len bytes of keying material (default 20)

Output for openssl ciphers -v

ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(256) Mac=AEAD
ECDHE-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(256) Mac=AEAD
ECDHE-RSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA384
ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA384
ECDHE-RSA-AES256-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(256)  Mac=SHA1
ECDHE-ECDSA-AES256-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(256)  Mac=SHA1
SRP-DSS-AES-256-CBC-SHA SSLv3 Kx=SRP      Au=DSS  Enc=AES(256)  Mac=SHA1
SRP-RSA-AES-256-CBC-SHA SSLv3 Kx=SRP      Au=RSA  Enc=AES(256)  Mac=SHA1
SRP-AES-256-CBC-SHA     SSLv3 Kx=SRP      Au=SRP  Enc=AES(256)  Mac=SHA1
DHE-DSS-AES256-GCM-SHA384 TLSv1.2 Kx=DH       Au=DSS  Enc=AESGCM(256) Mac=AEAD
DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH       Au=RSA  Enc=AESGCM(256) Mac=AEAD
DHE-RSA-AES256-SHA256   TLSv1.2 Kx=DH       Au=RSA  Enc=AES(256)  Mac=SHA256
DHE-DSS-AES256-SHA256   TLSv1.2 Kx=DH       Au=DSS  Enc=AES(256)  Mac=SHA256
DHE-RSA-AES256-SHA      SSLv3 Kx=DH       Au=RSA  Enc=AES(256)  Mac=SHA1
DHE-DSS-AES256-SHA      SSLv3 Kx=DH       Au=DSS  Enc=AES(256)  Mac=SHA1
DHE-RSA-CAMELLIA256-SHA SSLv3 Kx=DH       Au=RSA  Enc=Camellia(256) Mac=SHA1
DHE-DSS-CAMELLIA256-SHA SSLv3 Kx=DH       Au=DSS  Enc=Camellia(256) Mac=SHA1
ECDH-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(256) Mac=AEAD
ECDH-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(256) Mac=AEAD
ECDH-RSA-AES256-SHA384  TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(256)  Mac=SHA384
ECDH-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(256)  Mac=SHA384
ECDH-RSA-AES256-SHA     SSLv3 Kx=ECDH/RSA Au=ECDH Enc=AES(256)  Mac=SHA1
ECDH-ECDSA-AES256-SHA   SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=AES(256)  Mac=SHA1
AES256-GCM-SHA384       TLSv1.2 Kx=RSA      Au=RSA  Enc=AESGCM(256) Mac=AEAD
AES256-SHA256           TLSv1.2 Kx=RSA      Au=RSA  Enc=AES(256)  Mac=SHA256
AES256-SHA              SSLv3 Kx=RSA      Au=RSA  Enc=AES(256)  Mac=SHA1
CAMELLIA256-SHA         SSLv3 Kx=RSA      Au=RSA  Enc=Camellia(256) Mac=SHA1
PSK-AES256-CBC-SHA      SSLv3 Kx=PSK      Au=PSK  Enc=AES(256)  Mac=SHA1
ECDHE-RSA-DES-CBC3-SHA  SSLv3 Kx=ECDH     Au=RSA  Enc=3DES(168) Mac=SHA1
ECDHE-ECDSA-DES-CBC3-SHA SSLv3 Kx=ECDH     Au=ECDSA Enc=3DES(168) Mac=SHA1
SRP-DSS-3DES-EDE-CBC-SHA SSLv3 Kx=SRP      Au=DSS  Enc=3DES(168) Mac=SHA1
SRP-RSA-3DES-EDE-CBC-SHA SSLv3 Kx=SRP      Au=RSA  Enc=3DES(168) Mac=SHA1
SRP-3DES-EDE-CBC-SHA    SSLv3 Kx=SRP      Au=SRP  Enc=3DES(168) Mac=SHA1
EDH-RSA-DES-CBC3-SHA    SSLv3 Kx=DH       Au=RSA  Enc=3DES(168) Mac=SHA1
EDH-DSS-DES-CBC3-SHA    SSLv3 Kx=DH       Au=DSS  Enc=3DES(168) Mac=SHA1
ECDH-RSA-DES-CBC3-SHA   SSLv3 Kx=ECDH/RSA Au=ECDH Enc=3DES(168) Mac=SHA1
ECDH-ECDSA-DES-CBC3-SHA SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=3DES(168) Mac=SHA1
DES-CBC3-SHA            SSLv3 Kx=RSA      Au=RSA  Enc=3DES(168) Mac=SHA1
PSK-3DES-EDE-CBC-SHA    SSLv3 Kx=PSK      Au=PSK  Enc=3DES(168) Mac=SHA1
ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(128) Mac=AEAD
ECDHE-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(128) Mac=AEAD
ECDHE-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA256
ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA256
ECDHE-RSA-AES128-SHA    SSLv3 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA1
ECDHE-ECDSA-AES128-SHA  SSLv3 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA1
SRP-DSS-AES-128-CBC-SHA SSLv3 Kx=SRP      Au=DSS  Enc=AES(128)  Mac=SHA1
SRP-RSA-AES-128-CBC-SHA SSLv3 Kx=SRP      Au=RSA  Enc=AES(128)  Mac=SHA1
SRP-AES-128-CBC-SHA     SSLv3 Kx=SRP      Au=SRP  Enc=AES(128)  Mac=SHA1
DHE-DSS-AES128-GCM-SHA256 TLSv1.2 Kx=DH       Au=DSS  Enc=AESGCM(128) Mac=AEAD
DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH       Au=RSA  Enc=AESGCM(128) Mac=AEAD
DHE-RSA-AES128-SHA256   TLSv1.2 Kx=DH       Au=RSA  Enc=AES(128)  Mac=SHA256
DHE-DSS-AES128-SHA256   TLSv1.2 Kx=DH       Au=DSS  Enc=AES(128)  Mac=SHA256
DHE-RSA-AES128-SHA      SSLv3 Kx=DH       Au=RSA  Enc=AES(128)  Mac=SHA1
DHE-DSS-AES128-SHA      SSLv3 Kx=DH       Au=DSS  Enc=AES(128)  Mac=SHA1
DHE-RSA-SEED-SHA        SSLv3 Kx=DH       Au=RSA  Enc=SEED(128) Mac=SHA1
DHE-DSS-SEED-SHA        SSLv3 Kx=DH       Au=DSS  Enc=SEED(128) Mac=SHA1
DHE-RSA-CAMELLIA128-SHA SSLv3 Kx=DH       Au=RSA  Enc=Camellia(128) Mac=SHA1
DHE-DSS-CAMELLIA128-SHA SSLv3 Kx=DH       Au=DSS  Enc=Camellia(128) Mac=SHA1
ECDH-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(128) Mac=AEAD
ECDH-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AESGCM(128) Mac=AEAD
ECDH-RSA-AES128-SHA256  TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(128)  Mac=SHA256
ECDH-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH/ECDSA Au=ECDH Enc=AES(128)  Mac=SHA256
ECDH-RSA-AES128-SHA     SSLv3 Kx=ECDH/RSA Au=ECDH Enc=AES(128)  Mac=SHA1
ECDH-ECDSA-AES128-SHA   SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=AES(128)  Mac=SHA1
AES128-GCM-SHA256       TLSv1.2 Kx=RSA      Au=RSA  Enc=AESGCM(128) Mac=AEAD
AES128-SHA256           TLSv1.2 Kx=RSA      Au=RSA  Enc=AES(128)  Mac=SHA256
AES128-SHA              SSLv3 Kx=RSA      Au=RSA  Enc=AES(128)  Mac=SHA1
SEED-SHA                SSLv3 Kx=RSA      Au=RSA  Enc=SEED(128) Mac=SHA1
CAMELLIA128-SHA         SSLv3 Kx=RSA      Au=RSA  Enc=Camellia(128) Mac=SHA1
PSK-AES128-CBC-SHA      SSLv3 Kx=PSK      Au=PSK  Enc=AES(128)  Mac=SHA1
ECDHE-RSA-RC4-SHA       SSLv3 Kx=ECDH     Au=RSA  Enc=RC4(128)  Mac=SHA1
ECDHE-ECDSA-RC4-SHA     SSLv3 Kx=ECDH     Au=ECDSA Enc=RC4(128)  Mac=SHA1
ECDH-RSA-RC4-SHA        SSLv3 Kx=ECDH/RSA Au=ECDH Enc=RC4(128)  Mac=SHA1
ECDH-ECDSA-RC4-SHA      SSLv3 Kx=ECDH/ECDSA Au=ECDH Enc=RC4(128)  Mac=SHA1
RC4-SHA                 SSLv3 Kx=RSA      Au=RSA  Enc=RC4(128)  Mac=SHA1
RC4-MD5                 SSLv3 Kx=RSA      Au=RSA  Enc=RC4(128)  Mac=MD5 
PSK-RC4-SHA             SSLv3 Kx=PSK      Au=PSK  Enc=RC4(128)  Mac=SHA1
EDH-RSA-DES-CBC-SHA     SSLv3 Kx=DH       Au=RSA  Enc=DES(56)   Mac=SHA1
EDH-DSS-DES-CBC-SHA     SSLv3 Kx=DH       Au=DSS  Enc=DES(56)   Mac=SHA1
DES-CBC-SHA             SSLv3 Kx=RSA      Au=RSA  Enc=DES(56)   Mac=SHA1
  • What is the version of openssl . – Mongrel May 9 '16 at 6:36
  • 1.0.1-4ubuntu5.36 – Nishant Singh May 9 '16 at 6:37
  • Can you past the output of openssl ciphers -v – Mongrel May 9 '16 at 6:42
  • Do you have this package installed devscsripts & quilt – Mongrel May 9 '16 at 6:44
  • i don't have devscsripts and quilt installed – Nishant Singh May 9 '16 at 6:45
1

I advise you to use other method to test for SSLv2.

By now SSLv2 support has been discontinued in openssl, and it is the source of the error in your openssl command (I also have the same error in my side)

Try the methods described here:

How To Test SSLv2 DROWN Attack Vulnerability Using Python Script (And Solution to Fix the DROWN Attack on Apache and NginX)

Either you test the sites at https://test.drownattack.com/

or use the python script available here: https://github.com/tomato42/tlsfuzzer and described here script

From Debian: https://www.debian.org/security/2016/dsa-3500

SSLv2 protocol has already been dropped in the openssl package version 1.0.0c-2

  • i am running on openssl ` 1.0.1-4ubuntu5.36` , i don't need to update this ? right? – Nishant Singh May 9 '16 at 6:36
  • If you have a newer version, and being Ubuntu based in Debian, you do not have SSLv2 support in openssl, and thus no need to upgrade for this particular problem. – Rui F Ribeiro May 9 '16 at 6:38
  • well i checked upon the test.drownattack site , and it says supports SSLv2 vulnerable – Nishant Singh May 9 '16 at 6:39
  • Is the machine hosting the site the same where you are making tests? – Rui F Ribeiro May 9 '16 at 6:40
  • yes, the site is hosted on the same box – Nishant Singh May 9 '16 at 6:41
0

This is probably due to SSL2 being disabled in your implementation of OpenSSL.

I found this Debian bug report from 2010 to disable it, but you don't mention what distro you're using. I'm running Arch and I'm getting the same results as you, whereas on a CentOS 7 VM, -ssl2 works.

If you want to check for weak ciphers, consider using nmap instead:

$ nmap --script ssl-cert,ssl-enum-ciphers -p 443 www.example.com
Starting Nmap 6.25 ( http://nmap.org ) at 2013-01-01 00:00 CEST
Nmap scan report for www.example.com (127.0.0.1)
Host is up (0.090s latency).
rDNS record for 127.0.0.1: www.example.com
PORT    STATE SERVICE
443/tcp open  https
| ssl-cert: Subject: commonName=www.example.org
| Issuer: commonName=*******
| Public Key type: rsa
| Public Key bits: 1024
| Not valid before: 2010-01-23T00:00:00+00:00
| Not valid after:  2020-02-28T23:59:59+00:00
| MD5:   *******
|_SHA-1: *******
| ssl-enum-ciphers: 
|   SSLv3: 
|     ciphers: 
|       TLS_RSA_WITH_CAMELLIA_128_CBC_SHA - strong
|       TLS_RSA_WITH_CAMELLIA_256_CBC_SHA - strong
|       TLS_RSA_WITH_RC4_128_SHA - strong
|     compressors: 
|       NULL
|   TLSv1.0: 
|     ciphers: 
|       TLS_RSA_WITH_CAMELLIA_128_CBC_SHA - strong
|       TLS_RSA_WITH_CAMELLIA_256_CBC_SHA - strong
|       TLS_RSA_WITH_RC4_128_SHA - strong
|     compressors: 
|       NULL
|_  least strength: strong
  • I am running ubuntu 14.04 LTS – Nishant Singh May 9 '16 at 6:36
  • I confirm it too, see my previous post. Would this be considered a bug, still having the switch? – Rui F Ribeiro May 9 '16 at 6:37
  • As Ubuntu is based on Debian, then that's probably the bug report that disabled it in your distro. – garethTheRed May 9 '16 at 6:37
  • 1
    @RuiFRibeiro - I suppose it would. It was mentioned on the bottom of that bug report 5 years ago. The developers have probably bigger bugs to fix in OpenSSL ;-) – garethTheRed May 9 '16 at 6:41
  • I do not know whether to cry or to laugh... – Rui F Ribeiro May 9 '16 at 6:41
-2

You need to disable sslv2 in http.conf edit the file it should look like this.

SSLProtocol -all +SSLv3 +TLSv1 -SSLv2

Or

you can try this alternative command for checking openssl ciphers -v & past the output

  • I am trying to test my server for sslv2 vulnerability , linuxtoolkit.blogspot.in/2011/12/… – Nishant Singh May 9 '16 at 6:22
  • @Avinash : I am talking about checking it first via a remote server, how to first check if my server even supports – Nishant Singh May 9 '16 at 6:27
  • 1
    The OP isn't asking how to disable SSL. The question is why the -ssl2 option doesn't work. – garethTheRed May 9 '16 at 6:27

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