CVEs / CVE-2025-26399
CVE-2025-26399: SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability
- Known exploited in the CISA KEV catalog since 9 Mar 2026
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 90.1% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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 and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| SolarWinds Web Help Desk | 12.8.7 and below | — |
Exploitation
| In CISA KEV since | 9 Mar 2026 |
|---|---|
| Due date for US federal agencies | 12 Mar 2026 |
| Used in ransomware campaigns | Known |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-502 |
References
- CVE-2025-26399 on NVD
- CVE-2025-26399 in the CISA KEV catalog
- https://www.solarwinds.com/trust-center/security-advisories/cve-2025-26399 (cited by CISA)
- https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm (cited by CISA)
- https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm Release Notes
- https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-26399 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-26399 US Government Resource
- https://www.microsoft.com/en-us/security/blog/2026/02/06/active-exploitation-solarwinds-web-help-desk/ Third Party Advisory
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.