HTTP: Invalid ANI Block Size Parameter in Stream (2)

This signature detects invalid animated icon (ANI) files that contain an incorrect block size parameter. Malicious Web sites can post icon files that, when viewed in Internet Explorer Web browser, crash the browser's system. In some cases, attackers might be able to execute arbitrary code.

Extended Description

Microsoft Windows is prone to a stack buffer-overflow vulnerability because of insufficient format validation that occurs when handling malformed ANI cursor or icon files. An attacker can exploit this issue to execute arbitrary code with the privileges of an unsuspecting user. A successful attack can result in the compromise of affected user accounts and computers. This issue affects Windows Vista, Windows XP SP2, and Windows Server 2003 SP1 when running Internet Explorer 6 and 7; other versions and client applications may also be affected. Microsoft has recently disclosed that Outlook 2007 is not vulnerable, that Windows Mail on Vista is vulnerable in replying to or forwarding emails containing malicious ANI files, and that Outlook Express is vulnerable to this issue. Third-party applications such as browsers that handle ANI files and call the ANI rendering functionality in GDI pose an attack vector for this vulnerability.

Affected Products

Avaya messaging_application_server,Microsoft windows_server_2003_datacenter_x64_edition

References

BugTraq: 23194

CVE: CVE-2007-0038

URL: http://www.microsoft.com/technet/security/advisory/935423.mspx http://www.microsoft.com/technet/security/Bulletin/MS07-017.mspx

Short Name

HTTP:STC:IMG:ANI-BLOCK-STR2

Severity

Critical

Recommended

False

Recommended Action

Drop

HTTP: Invalid ANI Block Size Parameter in Stream (2)

Extended Description

Affected Products

References

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