[SA20114] FortressSSH SSH_MSG_KEXINIT Logging Buffer Overflow

TITLE:
FortressSSH SSH_MSG_KEXINIT Logging Buffer Overflow

SECUNIA ADVISORY ID:
SA20114

VERIFY ADVISORY:
http://secunia.com/advisories/20114/

CRITICAL:
Highly critical

IMPACT:
System access

WHERE:
>From remote

SOFTWARE:
Pragma FortressSSH 4.x
http://secunia.com/product/9961/

DESCRIPTION:
Gerry Eisenhaur has discovered a vulnerability in FortressSSH, which
can be exploited by malicious people to compromise a vulnerable
system.

The vulnerability is caused due to a boundary error within the
logging of the contents in SSH_MSG_KEXINIT messages sent by an SSH
client. This can be exploited to cause a stack-based buffer overflow
and may allow arbitrary code execution.

The vulnerability has been confirmed in version 4.0.7.20. Other
versions may also be affected.

SOLUTION:
Restrict access to trusted IP addresses only.

PROVIDED AND/OR DISCOVERED BY:
Gerry Eisenhaur

About:
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everybody keeping their systems up to date against the latest
vulnerabilities.

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