Sergio Alvarez has reported two vulnerabilities in avast!, which can be exploited by malicious people to compromise a vulnerable system.

The vulnerabilities are caused due to errors within the parsing of .CAB and .SIS files and can be exploited to cause heap-based buffer overflows via a specially crafted .CAB or .SIS file.

Successful exploitation may allow execution of arbitrary code.

The vulnerabilities reportedly affects versions prior to 4.7.766 for servers, 4.7.700 for the Managed Client product, and 4.7.1029 for Home/Professional editions.

Solution
Update to the latest versions.
Further details available to Secunia VIM customers

Provided and/or discovered by
Sergio Alvarez, n.runs AG

Changelog
Further details available to Secunia VIM customers

Original Advisory
avast!:
http://www.avast.com/eng/adnm-management-client-revision-history.html
http://www.avast.com/eng/avast-4-server-revision-history.html
http://www.avast.com/eng/avast-4-home_pro-revision-history.html

n.runs AG:
http://www.nruns.com/advisories/%5Bn.runs-SA-2007.008%5D%20-%20Avast!%20Antivirus%20CAB%20parsing%20Arbitrary%20Code%20Execution%20Advisory.txt
http://www.nruns.com/advisories/%5Bn.runs-SA-2007.009%5D%20-%20Avast!%20Antivirus%20SIS%20parsing%20Arbitrary%20Code%20Execution%20Advisory.txt

Other references
Further details available to Secunia VIM customers

Deep Links
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