CERT Advisory CA-2003-07 - Sendmail prior to 8.12.8 has a remote root vulnerability which can be exploited by a malicious mail message, allowing non-vulnerable MTA's to relay the exploit message to unpatched MTA's on an internal network. A successful attack against an unpatched sendmail system will not leave any messages in the logs. All Sendmail Pro, Sendmail Switch, and Sendmail for NT are also vulnerable. Fix available here.
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