On 2026-03-09, CISA added CVE-2025-26399 (SolarWinds Web Help Desk) to its Known Exploited Vulnerabilities (KEV) Catalog [2]. The vulnerability is listed in the catalog as "SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability" [2]. CISA requires remediation in accordance with vendor mitigation instructions; see the original text in the body for specific requirements [2].
Backfill: this event became public on Mar 9, 2026 and we added it on Nov 10, 2026. It is not a new event.
CISA Adds SolarWinds Web Help Desk Vulnerability CVE-2025-26399 to Known Exploited Vulnerabilities Catalog
1 min read
- Disclosed
- Mar 9, 2026
- Published
- Nov 10, 2026
- Last updated
- Nov 8, 2026
- CVSS basis
- Our assessment
- 90.6%, higher than 100% of CVEs
- Exploitation and patch status
- ExploitedKEV
- Attack vector
- Vulnerability status
- Actor type
- Motivation
On this page
30-second summary
What happened
Who is affected
Industries mainly affected: Government, Cross-industry
What to do nowOur advice
CISA requires remediation in accordance with vendor mitigation instructions; see the original text in the body for specific requirements [2]
Timeline
Technical details
CISA KEV Listing Record
On 2026-03-09, CISA added CVE-2025-26399 to the catalog for SolarWinds Web Help Desk [2].
Original Technical Description
SolarWinds Web Help Desk contain a deserialization of untrusted data vulnerability in AjaxProxy that could allow an attacker to run commands on the host machine. [2]
Official Requirements
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. [2]
Individual Vulnerability Record
The U.S. National Vulnerability Database (NVD) provides an independent vulnerability record and description for CVE-2025-26399. [1]
References
Official / primary3
- [1]
“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 b”
- [2]
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