CRITICAL · CVSS 9.8 Used in ransomware attacks

CVE-2025-40554

SolarWinds Web Help Desk

SolarWinds Web Help Desk was found to be susceptible to an authentication bypass vulnerability that, if exploited, could allow an attacker to invoke specific actions within Web Help Desk.

CVSS
9.8
CRITICAL
EPSS
60.6%
30-day exploitation
Ransomware groups
1
recorded exploiting
Published
28 Jan 2026
CWE-1390

Ransomware groups exploiting CVE-2025-40554

Qilin 2,294 victims tracked

Qilin ransomware was first observed in July of 2022. Qilin Ransomware is written in Golang and supports multiple encryption modes; all of which are controlled by the operator. Qilin actors practice double extortion – demanding payment for a decryptor, as well

Exploitation is attributed to these groups across their recorded activity. It does not follow that every organisation they listed was reached through CVE-2025-40554 — the source data does not record an entry point per incident.

Exploitation status

EPSS — exploitation probability

FIRST puts the probability of exploitation activity in the next 30 days at 60.6%, which is higher than 99.1% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Recent listings by these groups

Disclosures from the groups above, newest first.

Frequently asked questions

Is CVE-2025-40554 being exploited by ransomware groups?

Yes. CVE-2025-40554 is recorded as exploited by Qilin. Between them these groups account for 2,294 victim disclosures in this database.

What does CVE-2025-40554 affect?

CVE-2025-40554 affects SolarWinds Web Help Desk. SolarWinds Web Help Desk was found to be susceptible to an authentication bypass vulnerability that, if exploited, could allow an attacker to invoke specific actions within Web Help Desk.

How severe is CVE-2025-40554?

CVE-2025-40554 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 60.6%, higher than 99.1% of all scored vulnerabilities. It is not currently in the CISA Known Exploited Vulnerabilities catalog.

How should organisations respond to CVE-2025-40554?

Apply the vendor patch for SolarWinds Web Help Desk as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.