CVE-2025-26399
SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 12 March 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 89.50% probability · 100th percentile
- CISA KEV
- Listed 9 March 2026 · due 12 March 2026 · used in ransomware campaigns
- Weakness
- CWE-502
- Affected
- solarwinds/web help desk
- Source
- psirt@solarwinds.com
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://www.solarwinds.com/trust-center/security-advisories/cve-2025-26399 ; https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm ; https://nvd.nist.gov/vuln/detail/CVE-2025-26399
References
- https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htmRelease Notes
- https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-26399Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-26399US Government Resource
- https://www.microsoft.com/en-us/security/blog/2026/02/06/active-exploitation-solarwinds-web-help-desk/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.