CVE-2025-40553 SolarWinds Web Help Desk Deserialization of Untrusted Data Remote Code Execution Vulnerability

Critical 9.8 Published 28 Jan 2026 Updated 27 Feb 2026

Unauthenticated attackers can achieve remote code execution on SolarWinds Web Help Desk hosts via unsafe deserialization of untrusted data.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2025-40553?

CVE-2025-40553 is a critical unsafe deserialization vulnerability in SolarWinds Web Help Desk, published on 28 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-502

Which versions are affected by CVE-2025-40553?

It affects 1 product.

Products include Solarwinds Web Help Desk.

How do I fix CVE-2025-40553?

No fix has been published for CVE-2025-40553 yet. Limit exposure of the affected software until one is available.

Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.

Is CVE-2025-40553 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-40553 exists.

Sources

Also known as GHSA-5gq3-mh83-6m28.