Kmail 1.9.1 on KDE 3.5.2, with "Prefer HTML to Plain Text" enabled, allows remote attackers to cause a denial of service (crash) via an HTML e-mail with certain table and frameset tags that trigger a segmentation fault, possibly involving invalid free or delete operations.

KMail 1.9.5 and earlier does not properly use the --status-fd argument when invoking GnuPG, which prevents KMail from visually distinguishing between signed and unsigned portions of OpenPGP messages with multiple components, which allows remote attackers to forge the contents of a message without detection.