In Xymon through 4.3.28, a buffer overflow vulnerability exists in the csvinfo CGI script. The overflow may be exploited by sending a crafted GET request that triggers an sprintf of the srcdb parameter.
In Xymon through 4.3.28, a stack-based buffer overflow vulnerability exists in the alert acknowledgment CGI tool because of expansion in acknowledge.c.
In Xymon through 4.3.28, a stack-based buffer overflow vulnerability exists in the history viewer component via a long hostname or service parameter to history.c.
Multiple cross-site scripting (XSS) vulnerabilities in Xymon 4.1.x, 4.2.x, and 4.3.x before 4.3.25 allow (1) remote Xymon clients to inject arbitrary web script or HTML via a status-message, which is not properly handled in the "detailed status" page, or (2) remote authenticated users to inject arbitrary web script or HTML via an acknowledgement message, which is not properly handled in the "status" page.