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."
HTMLTokenizer::scriptHandler in Konqueror in KDE 3.5.9 and 3.5.10 allows remote attackers to cause a denial of service (application crash) via an invalid document.load call that triggers use of a deleted object. NOTE: some of these details are obtained from third party information.
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.