Secunia

Secunia Research has discovered two vulnerabilities in avast!, which can be exploited by malicious people to compromise a vulnerable system.

1) An input validation error during extraction of ACE archives for scanning can be exploited to write files to arbitrary directories. This can be exploited when scanning a malicious archive containing a file that has the "/../" directory traversal sequence or an absolute path in its filename.

2) A boundary error in the scanning of ACE archives can be exploited to cause a stack-based buffer overflow when scanning a specially crafted ACE archive containing a file with a filename of more than 290 bytes.

Successful exploitation allows execution of arbitrary code and writing of files to arbitrary directories, but requires ACE archive scanning to be enabled.

The vulnerabilities are related to:
SA14359

The vulnerabilities have been confirmed in avast! Home/Professional Edition version 4.6.665 and Server Edition version 4.6.460. The vendor has reported that avast! Managed Client is also affected.

Solution
Home/Professional Edition:
Further details available in Customer Area

Provided and/or discovered by
Tan Chew Keong, Secunia Research.

Changelog
Further details available in Customer Area

Original Advisory
Secunia Research:
http://secunia.com/secunia_research/2005-20/advisory/

Other references
Further details available in Customer Area

Deep Links
Links available in Customer Area