CVE-2025-40551

SolarWinds Web Help Desk: Deserialization of Untrusted Data

As of , CVE-2025-40551 in SolarWinds Web Help Desk is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 3 February 2026
US federal deadline
6 February 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.84Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
1 Metasploit module
Fix
Vendor advice: www.solarwinds.comLinks below, from CISA's entry.

What CISA says to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA's required action

What the flaw is

SolarWinds Web Help Desk contains a deserialization of untrusted data 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.

CISA's 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.

The CVE record's description, from SolarWinds

CVE published
28 January 2026
Assigned by
SolarWinds
CVSS
9.8 Critical (CVSS 3.1, from the CNA)
CWE-502
Deserialization of Untrusted Data
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

  • Metasploit: SolarWinds Web Help Desk unauthenticated RCEexploit module, rank great

Web Help Desk: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2025-26399Deserialization of Untrusted DataSolarWinds Web Help DeskPatch nowRansomware use, listed within a year0.90
CVE-2025-40536Security Control BypassSolarWinds Web Help DeskPatch this weekMetasploit module; EPSS 0.740.74
CVE-2024-28987Hardcoded CredentialSolarWinds Web Help DeskPatch this weekMetasploit module; EPSS 0.930.93
CVE-2024-28986Deserialization of Untrusted DataSolarWinds Web Help DeskPatch this weekEPSS 0.850.85

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