Clam AntiVirus is "a multi-platform anti-virus toolkit released under the GNU Public License. ClamAV is often integrated into e-mail gateways and used to scan e-mail messages for viruses. PE, or portable executable, is the executable file format on Microsoft Windows systems. MEW is one of the many executable packers that is supported by ClamAV". Remote exploitation of an integer overflow vulnerability in Clam AntiVirus' ClamAV, as included in various vendors' operating system distributions, allows attackers to execute arbitrary code with the privileges of the affected process.

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