Watch me do my headless chicken imitation!

Sendmail, Inc. has issued an advisory concerning its MTA product: Sendmail.

The vendors advisory is available here and a better explanation of the actual vulnerability is available here.

Short version: An attacker can exploit a buffer overflow via specially crafted message headers and possibly execute code due to a flawed security check in Sendmail versions 8.12.7 and below.

Really simple version: An attacker can break into your computer by sending e-mail.