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
- 90.12% probability · 100th percentile
- Public exploits
- None in Exploit-DB
- 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
EPSS 90.1% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
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, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.