Cade Cairns of Securityfocus discovered a vulnerability in the sendmail program, the widely spread MTA used in Unix- and Unix-like systems. A local user can write arbitrary data to the process memory, resulting in user-controlled code to be executed as user root. Please note that this is a local vulnerability: Local shell access is needed for the attacker to be able to take advantage of this error. The /usr/sbin/sendmail program is installed set-uid root in most installations. This special privilege is needed for the sendmail program to operate properly. The attack pattern involves running sendmail to make use of the setuid-bit. Please note that this is the first sendmail security problem since 1997.