AUSCERT External Security Bulletin Redistribution

                   ESB-2003.0687 -- CERT Advisory Notice
        Clarifications regarding recent vulnerabilities in OpenSSH
                             30 September 2003


        AusCERT Security Bulletin Summary

Product:                OpenSSH
Publisher:              CERT/CC
Impact:                 Denial of Service
                        Root Compromise
Access Required:        Remote
CVE Names:              CAN-2003-0693, CAN-2003-0786, CAN-2003-0787

Ref:                    AL-2003.16

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CERT Advisory Notice: Clarifications regarding recent vulnerabilities in OpenSSH

The CERT/CC has received queries regarding several recent OpenSSH
vulnerabilities.  We are sending this message to help ensure that
administrators have not overlooked one or more of these vulnerabilities.

There have been several recent vulnerabilities affecting OpenSSH. They

VU#333628 - OpenSSH contains buffer management errors

    This issue addresses two releases of OpenSSH to resolve multiple 
    issues in the buffer management code. It is unclear if these issues 
    are exploitable, but they are resolved in version 3.7.1. Note that 
    there are other additional flaws in the buffer management code as 
    reported by Openwall GNU/*/Linux in 
    http://www.kb.cert.org/vuls/id/JARL-5RFQQZ. These four additional 
    flaws are believed to be relatively minor, and are scheduled to be
    included in the next version of OpenSSH.

VU#602204 - OpenSSH PAM challenge authentication failure

   Under non-standard configurations, portable versions of OpenSSH 3.7p1 
   and 3.7.1p1 are vulnerable to a remotely exploitable vulnerability.
   Exploitation of this vulnerability may lead to a remote attacker 
   gaining privileged access to the server, in some cases root access.

VU#209807 - Portable OpenSSH server PAM conversion stack corruption

   There is a vulnerability in portable versions of OpenSSH 3.7p1 and
   3.7.1p1 that may permit an attacker to corrupt the PAM conversion
   stack. The complete impact of this vulnerability is unclear, but may 
   lead to privilege escalation, or a denial of service.

Please check the vulnerability notes for resolutions and additional 

Thank you.

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