CVE-2025-40536
CVE-2025-40536 is a security flaw in SolarWinds Web Help Desk, SolarWinds’ IT management software. Attackers can get past a security protection in SolarWinds Web Help Desk. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 12 Feb 2026.[1]
SolarWinds Web Help Desk is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. SolarWinds has published a fix or advice.
Description
CISA calls it a security control bypass in SolarWinds Web Help Desk. In its words: “SolarWinds Web Help Desk contains a security control bypass vulnerability that could allow an unauthenticated attacker to gain access to certain restricted functionality.”[1]
The underlying weakness is protection mechanism failure (CWE-693), in MITRE’s list of common software weaknesses.[2]
It scores 9.8 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; SolarWinds’s advisory has them[3]. CISA names the product as SolarWinds Web Help Desk.
Most families won’t have SolarWinds Web Help Desk; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 12 Feb 2026, 15 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 15 Feb 2026 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 74%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
SolarWinds has published a fix or advice.[3] CISA’s 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.”[1]
- Check whether you use it.SolarWinds Web Help Desk is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 15 Feb 2026 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 9.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 74%.[4] |
See also
Other SolarWinds Web Help Desk flaws
- CVE-2025-26399: deserialization of untrusted data ·
- CVE-2025-40551: deserialization of untrusted data ·
- CVE-2024-28987: hardcoded credential ·
- CVE-2024-28986: deserialization of untrusted data ·
Other SolarWinds flaws
- CVE-2026-28318, SolarWinds Serv-U: uncontrolled resource consumption ·
- CVE-2024-28995, SolarWinds Serv-U: path traversal ·
- CVE-2021-35247, SolarWinds Serv-U: improper input validation ·
- CVE-2021-35211, SolarWinds Serv-U: remote code execution ·
- CVE-2020-10148, SolarWinds Orion: authentication bypass ·
Other protection mechanism failure flaws
- CVE-2026-58704, Google Pixel: improper authorization ·
- CVE-2026-32202, Microsoft Windows: protection mechanism failure ·
- CVE-2026-21513, Microsoft Windows: MSHTML framework protection mechanism failure ·
- CVE-2026-21510, Microsoft Windows: shell protection mechanism failure ·
- CVE-2025-0411, 7-Zip: mark of the web bypass ·
Added the same day
- CVE-2026-20700, Apple devices: multiple buffer overflow ·
- CVE-2025-15556, Notepad++: download of code without integrity check ·
- CVE-2024-43468, Microsoft Configuration Manager: SQL injection ·
Every SolarWinds flaw on CISA’s list · Everything added in February 2026
References
- ^ Cybersecurity and Infrastructure Security Agency. “SolarWinds Web Help Desk Security Control Bypass Vulnerability”. Known Exploited Vulnerabilities Catalog, added 12 Feb 2026.
- ^ National Institute of Standards and Technology. “CVE-2025-40536 Detail”. National Vulnerability Database, published 28 Jan 2026.
- ^ SolarWinds. Advisories and fixes: documentation.solarwinds.com, solarwinds.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.736, percentile 99.5, 31 Oct 2026.
- CVE Program. “CVE-2025-40536”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.