iDEFENSE has discovered some vulnerabilities in XFree86, which can be exploited by malicious, local users to gain escalated privileges.

The vulnerabilities are caused due to boundary errors in the "ReadFontAlias()" and "CopyISOLatin1Lowered()" functions when parsing a "font.alias" file. This can be exploited to cause a buffer overflow by constructing a malicious "font.alias" file.

Successful exploitation allows execution of arbitrary code with root privileges.

The vulnerabilities have been reported in versions 4.1.0 through 4.3.0. Prior versions may also be affected.

Solution
Apply patch or update to version 4.3.99.903 Release Candidate.
Further details available in Customer Area

Provided and/or discovered by
Greg MacManus, iDEFENSE Labs.

Changelog
Further details available in Customer Area

Original Advisory
http://www.idefense.com/application/poi/display?id=72&type=vulnerabilities
http://www.idefense.com/application/poi/display?id=73&type=vulnerabilities

Other references
Further details available in Customer Area

Deep Links
Links available in Customer Area