1 Reply Latest reply on Mar 8, 2016 6:49 AM by jeph.yang

    VA issue related to inbound email port

    sreeja_bhat

      Hi Jive,

       

      We are using inbound email for our Ricoh jive application and we are getting some security issue related to the port 2510/2500.Please find below the reported issue and suggested fix.

       

      Issue:

      It is possible to obtain sensitive information from the remote host with SSL/TLS-enabled services. The remote host is affected by a man-in-the-middle (MitM) information disclosure vulnerability known as POODLE. The vulnerability is due to the way SSL 3.0 handles padding bytes when decrypting messages encrypted using block ciphers in cipher block chaining (CBC) mode. MitM attackers can decrypt a selected byte of a cipher text in as few as 256 tries if they are able to force a victim application to repeatedly send the same data over newly created SSL 3.0 connections. As long as a client and service both support SSLv3, a connection can be 'rolled back' to SSLv3, even if TLSv1 or newer is supported by the client and service. The TLS Fallback SCSV mechanism prevents 'version rollback' attacks without impacting legacy clients; however, it can only protect connections when the client and service support the mechanism. Sites that cannot disable SSLv3 immediately should enable this mechanism. This is a vulnerability in the SSLv3 specification, not in any particular SSL implementation. Disabling SSLv3 is the only way to completely mitigate the vulnerability.

       

      The remote service supports the use of the RC4 cipher. The remote host supports the use of RC4 in one or more cipher suites. The RC4 cipher is flawed in its generation of a pseudo-random stream

      of bytes so that a wide variety of small biases are introduced into the stream, decreasing its randomness. If plaintext is repeatedly encrypted (e.g., HTTP cookies), and an attacker is able to obtain many (i.e., tens of millions) ciphertexts, the attacker may be able to derive the plaintext.

       

      Suggested Fixes:

      Disable SSLv3. Services that must support SSLv3 should enable the TLS Fallback SCSV mechanism until SSLv3 can be disabled.

      Reconfigure the affected application, if possible, to avoid use of RC4 ciphers. Consider using TLS 1.2 with AES-GCM suites subject to browser and web server support.

       

      We had raised a similar case earlier  Case #253415 for these ports 2510/2500. Please let us know if we have to configure TLS or can we ignore this as there is no potential for Man in the Middle threat for this.

       

      We had raised the same case earlier Case #293115. We have not got any further response on that, hence raising this new case.

       

      Thanks,

      Sreeja

        • Re: VA issue related to inbound email port

          Hi Sreeja,

           

          Thanks for raising this question for the security concerns around port 2510/2500. I did review case 253415 and see that the resolution comment was:

           

          The SMTP server used for advanced incoming is only in communication with the Jive instance and is behind your firewall. There is therefore no potential for the perceived "Man-in-the-middle" threat.

           

          For the second case, I see an unrelated issue for a different customer, but I believe you're actually referring to another discussion thread:  VA issue related to inbound email port.  Given the sensitive nature of the issue, I would recommend submitting a support case in order to investigate this further with our security team.

           

          Let me know if you had any other questions.

           

          Regards,

          Jeph Yang