Updated Sendmail packages that fix a potentially-exploitable vulnerability are now available.
Sendmail is a widely used Mail Transport Agent (MTA) and is included in all Red Hat Enterprise Linux distributions. There is a bug in the prescan() function of Sendmail versions prior to and including 8.12.9. The sucessful exploitation of this bug can lead to heap and stack structure overflows. Although no exploit currently exists, this issue is locally exploitable and may also be remotely exploitable. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2003-0694 to this issue. All users are advised to update to these erratum packages containing a backported patch which corrects these vulnerabilities. Red Hat would like to thank Michal Zalewski for finding and reporting this issue.