CVE-2025-26399: SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability

Critical severity, CVSS 9.8. Actively exploited: in CISA KEV since 2026-03-09. EPSS: 89.5% chance of exploitation in the next 30 days.

SolarWinds Web Help Desk was found to be susceptible to an unauthenticated AjaxProxy deserialization remote code execution vulnerability that, if exploited, would allow an attacker to run commands on the host machine. This vulnerability is a patch bypass of CVE-2024-28988, which in turn is a patch bypass of CVE-2024-28986.

Affected products

• SolarWinds Web Help Desk: up to and including 12.8.6; version 12.8.7 only

Published 2025-09-23. Last modified 2026-06-17.