rendering/render_replaced.cpp in Konqueror in KDE before 4.9.3 allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted web page, related to "trying to reuse a frame with a null part."
start_kdeinit in KDE 3.5.5 through 3.5.9, when installed setuid root, allows local users to cause a denial of service and possibly execute arbitrary code via "user-influenceable input" (probably command-line arguments) that cause start_kdeinit to send SIGUSR1 signals to other processes.
backend/session.c in KDM in KDE 3.3.0 through 3.5.7, when autologin is configured and "shutdown with password" is enabled, allows remote attackers to bypass the password requirement and login to arbitrary accounts via unspecified vectors.