CVE-2025-26399
SolarWinds Web Help Desk was found to be susceptible to an unauthenticated AjaxProxy deserialization remote code execution vulnerability that, if…
Browse: All 2025 CVEs · All vendors
- CVSS score
- 9.8 Critical
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- CISA KEV
- Yes — actively exploited (added 2026-03-09, remediation due 2026-03-12)
- Ransomware
- Known ransomware campaign use
- Weakness (CWE)
- CWE-502
- Published
- 2025-09-23
- Last modified
- 2026-06-17
- NVD status
- Analyzed
Description
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
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Federal remediation deadline: 2026-03-12.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score.
References
- https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm
- https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-26399
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-26399
- https://www.microsoft.com/en-us/security/blog/2026/02/06/active-exploitation-solarwinds-web-help-desk/
FAQ
Is CVE-2025-26399 actively exploited?
Yes. CISA added CVE-2025-26399 to its Known Exploited Vulnerabilities (KEV) catalog on 2026-03-09, with a federal remediation deadline of 2026-03-12. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2025-26399?
CVE-2025-26399 has a CVSS base score of 9.8 (Critical). Its vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Related vulnerabilities
- CVE-2025-40536 — SolarWinds Web Help Desk
- CVE-2025-40551 — SolarWinds Web Help Desk
- CVE-2024-28987 — SolarWinds Web Help Desk
- CVE-2024-28986 — SolarWinds Web Help Desk
- CVE-2026-28318 — SolarWinds Serv-U
- CVE-2024-28995 — SolarWinds Serv-U
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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