What is CVE-2025-40551?

CVE-2025-40551 is a critical-severity vulnerability in Solarwinds Web Help Desk, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-01-28.

How severe is CVE-2025-40551?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2025-40551 known to be exploited?

Yes. CVE-2025-40551 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-02-03), indicating it is being actively exploited. 1 public proof-of-concept repositories are indexed.

Deserialization in Solarwinds Web Help Desk

CVE-2025-40551

SolarWinds Web Help Desk was found to be susceptible to an untrusted data deserialization vulnerability that could lead to remote code execution, which would allow an attacker to run commands on the host machine. This could be exploited wi…

Vulnerability class: Insecure Deserialization

EPSS: 0.870 (99.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Solarwinds Web Help Desk — versions 12.8.8 HF1 and below

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2026-02-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2026-02-06.

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.

Public proof-of-concept exploits

rapid7/metasploit-framework

References

www.solarwinds.com/trust-center/security-advisories/CVE-2025-40551 (vendor-advisory, patch)
documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_20… (release-notes)

Frequently asked questions

What is CVE-2025-40551?: CVE-2025-40551 is a critical-severity vulnerability in Solarwinds Web Help Desk, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-01-28.
How severe is CVE-2025-40551?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-40551 known to be exploited?: Yes. CVE-2025-40551 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-02-03), indicating it is being actively exploited. 1 public proof-of-concept repositories are indexed.