Multiple cross-site scripting (XSS) vulnerabilities in Webcit before 7.11 allow remote attackers to inject arbitrary web script or HTML via (1) the who parameter to showuser; and other vectors involving (2) calendar mode, (3) bulletin board mode, (4) room names, and (5) uploaded file names.

Cross-site request forgery (CSRF) vulnerability in Webcit before 7.11 allows remote attackers to modify configurations and perform other actions as arbitrary users via unspecified vectors.

Format string vulnerability in the lprintf function in Citadel/UX 6.27 and earlier allows remote attackers to execute arbitrary code via format string specifiers sent to the server.

Buffer overflow in Citadel/UX 6.23 and earlier allows remote attackers to cause a denial of service via a long username.

Buffer overflow in (1) lprintf and (2) cprintf in sysdep.c of Citadel/UX 5.90 and earlier allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via attacks such as a long HELO command to the SMTP server.