CVE-2026-80465 Auth bypass in Mendix SAML (Mendix 10 compatible)
Unauthenticated attackers can hijack accounts in specific SSO configurations due to improper SAML response signature validation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-80465?
CVE-2026-80465 is a high-severity authentication bypass vulnerability in Siemens Mendix SAML (Mendix 10 compatible), published on 3 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A vulnerability has been identified in Mendix SAML (Mendix 10 compatible) (All versions < V4.2.4), Mendix SAML (Mendix 11 compatible) (All versions < V4.2.4), Mendix SAML (Mendix 9.24 compatible) (All versions < V3.6.29). Affected versions of the module do not properly validate the SAML response signature. This could allow unauthenticated remote attackers to hijack an account (session) in specific SSO configurations.
Weakness: CWE-347
Which versions are affected by CVE-2026-80465?
How do I fix CVE-2026-80465?
No fix has been published for CVE-2026-80465 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-80465 being exploited?
There is no known exploitation of CVE-2026-80465 in the wild and no public exploit code.
Sources
Also known as GHSA-249p-r5w7-w969.