Description
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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | xymon | 4.3.25-1 | — |
| Debian 13 | xymon | 4.3.25-1 | — |
| Debian 12 | xymon | 4.3.25-1 | — |
| Debian 8 | xymon | 4.3.17-6+deb8u1 | DSA-3495-1 |
| Debian 7 | xymon | 4.3.0~beta2.dfsg-9.1+deb7u1 | DLA-488-1 |
Advisories 2
- DLA-488-1 xymon - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3495-1 xymon - security update Debian Security (DSA / DLA) · Mar 9, 2026