How severe is CVE-2025-40551?

CVE-2025-40551 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2025-40551?

Affected package information for CVE-2025-40551 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2025-40551?

No fixed version has been published for CVE-2025-40551 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2025-40551 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-40551 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-40551?

CVE-2025-40551 has an EPSS (Exploit Prediction Scoring System) score of 87.9%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2025-40551 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2025-40551 (SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2026-02-03. CISA required all US federal civilian agencies to remediate this vulnerability by 2026-02-06. The required action was: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2025-40551?

CVE-2025-40551 is classified as Deserialization of Untrusted Data (CWE-502). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2025-40551?

CVE-2025-40551 affects solarwinds web help desk. Check the affected-products list on this page against your deployed version to confirm exposure.

Is there exploit tooling available for CVE-2025-40551?

A Nuclei detection template exists for CVE-2025-40551, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2025-40551 published, and has it been updated?

CVE-2025-40551 was published on January 28, 2026 and was last updated on February 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2025-40551: Web Help Desk Deserialization of Untrusted Data…

EPSS Exploitation Probability

via FIRST.org ↗

87.9%probability of exploitation in next 30 days

Very High Risk99th percentile+0.90%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

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 without authentication.

Affected Products

1 product · 1 configurations

Application

web help desksolarwinds

< 2026.1

range

Frequently Asked Questions

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 without authentication.

O3 Security · Impact-Aware SCA

Is CVE-2025-40551 in your stack?

O3 detects CVE-2025-40551 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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