Update the Mendix SAML module to V4.2.3 or later (Mendix 10/11 compatible) or V3.6.27 or later (Mendix 9.24 compatible). Minimize network exposure by ensuring affected devices are not internet-facing. Locate control system networks behind firewalls and isolate from business networks. Use updated VPNs for remote access. Perform impact analysis and risk assessment before deploying defensive measures.
Quick answers
What is CVE-2026-80465?
Update the Mendix SAML module to V4.2.3 or later (Mendix 10/11 compatible) or V3.6.27 or later (Mendix 9.24 compatible). Minimize network exposure by ensuring affected devices are not internet-facing. Locate control system networks behind firewalls and isolate from business networks. Use updated VPNs for remote access. Perform impact analysis and risk assessment before deploying defensive measures.
How severe is CVE-2026-80465?
high, CVSS 8.7
Is CVE-2026-80465 known to be exploited?
It is not marked known-exploited in this record.
How should CVE-2026-80465 be mitigated?
Update the Mendix SAML module to V4.2.3 or later (Mendix 10/11 compatible) or V3.6.27 or later (Mendix 9.24 compatible). Minimize network exposure by ensuring affected devices are not internet-facing. Locate control system networks behind firewalls and isolate from business networks. Use updated VPNs for remote access. Perform impact analysis and risk assessment before deploying defensive measures.
CVSS
8.7
Vendor
Siemens
Published
Sep 30, 2026 · 08:05
Patch
Unknown / not confirmed
Affected products
Siemens Mendix SAML
Mitigation
Update the Mendix SAML module to V4.2.3 or later (Mendix 10/11 compatible) or V3.6.27 or later (Mendix 9.24 compatible). Minimize network exposure by ensuring affected devices are not internet-facing. Locate control system networks behind firewalls and isolate from business networks. Use updated VPNs for remote access. Perform impact analysis and risk assessment before deploying defensive measures.
A vulnerability in the Siemens Mendix SAML module stems from improper verification of cryptographic signatures in SAML responses. Tracked as CVE-2026-80465 with a CVSS 3.1 base score of 8.7 (HIGH), the flaw could allow unauthenticated remote attackers to hijack user accounts in specific Single Sign-On configurations. Affected versions include Mendix SAML (Mendix 10/11 compatible) below V4.2.3 and Mendix SAML (Mendix 9.24 compatible) below V3.6.27. Siemens ProductCERT reported the issue to CISA, and vendor fixes are available via the Mendix marketplace. Siemens and CISA recommend minimizing network exposure and updating to the latest patched versions.