[SA22591] Sophos Anti-Virus RAR and CHM Denial of Service Vulnerabilities

TITLE:
Sophos Anti-Virus RAR and CHM Denial of Service Vulnerabilities

SECUNIA ADVISORY ID:
SA22591

VERIFY ADVISORY:
http://secunia.com/advisories/22591/

CRITICAL:
Moderately critical

IMPACT:
DoS

WHERE:
>From remote

SOFTWARE:
Sophos Anti-Virus for Windows 6.x
http://secunia.com/product/12449/
Sophos Anti-Virus 5.x
http://secunia.com/product/5390/
Sophos Anti-Virus 4.x
http://secunia.com/product/5391/
Sophos Anti-Virus Small Business Edition
http://secunia.com/product/9822/

DESCRIPTION:
Some vulnerabilities have been reported in Sophos Anti-Virus, which
can be exploited by malicious people to cause a DoS (Denial of
Service).

1) An unspecified error when processing RAR archives may in certain
cases cause an infinite loop in the scanning engine and consume all
available CPU resources.

2) An unspecified error when processing CHM files may in certain
cases result in a heap-based buffer overflow.

3) An unspecified error when processing CHM files with long names may
cause a memory corruption.

SOLUTION:
The vulnerabilities will reportedly be fixed in December 2006.

PROVIDED AND/OR DISCOVERED BY:
The vendor credits iDefense.

ORIGINAL ADVISORY:
Sophos:
http://www.sophos.com/support/knowledgebase/article/7609.html

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About:
This Advisory was delivered by Secunia as a free service to help
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vulnerabilities.

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