CVE-2026-80465 Siemens CVE debrief

Who should care

Organizations using Mendix platforms with SAML-based SSO configurations should review and update their Mendix SAML module versions to prevent potential session hijacking attacks. This includes verifying SAML response signature validation in affected configurations and implementing compensating controls for SSO configurations, such as additional authentication factors, if necessary. Security teams and vulnerability management teams should prioritize this vulnerability due to its potential for session hijacking in specific SSO configurations. IT operators and administrators of Mendix platforms should also be aware of the potential risks and take necessary actions to mitigate them. Additionally, organizations should ensure that their security teams are monitoring for potential attacks and have incident response plans in place in case of a breach. This vulnerability affects Mendix SAML (Mendix 10 compatible) (All versions < V4.2.3), Mendix SAML (Mendix 11 compatible) (All versions < V4.2.3), and Mendix SAML (Mendix 9.24 compatible) (All versions < V3.6.27). Affected organizations should assign an owner for follow-up and track exceptions, retest remediated assets, and close the item only after evidence is documented. They should also review compensating controls for exposed systems while remediation is scheduled and verified, and check relevant monitoring, detection, and logs for exposed assets that need extra review. Finally, organizations should plan vendor-supported updates or mitigations through normal change control where exposure is confirmed. This may involve coordinating with vendors, testing updates, and implementing them in a timely manner to minimize potential disruptions. By taking these steps, organizations can reduce the risk of session hijacking attacks and protect their Mendix platforms with SAML-based SSO configurations. It's also recommended to confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. This can help ensure that the necessary actions are taken to mitigate the vulnerability and minimize potential disruptions. Overall, organizations should take a proactive and multi-faceted approach to

Technical summary

The Mendix SAML module vulnerability (CVE-2026-80465) allows unauthenticated remote attackers to hijack an account (session) in specific SSO configurations due to improper validation of the SAML response signature. Affected versions include Mendix SAML (Mendix 10 compatible) (All versions < V4.2.3), Mendix SAML (Mendix 11 compatible) (All versions < V4.2.3), and Mendix SAML (Mendix 9.24 compatible) (All versions < V3.6.27).

Defensive priority

High priority due to potential for session hijacking in specific SSO configurations.

Recommended defensive actions

• Review Mendix SAML module versions and update to V4.2.3 or later for Mendix 10 and 11 compatible versions, or V3.6.27 or later for Mendix 9.24 compatible version.
• Verify SAML response signature validation in affected configurations.
• Implement compensating controls for SSO configurations, such as additional authentication factors.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

Evidence from official CVE Program record and NIST NVD detail page indicates vulnerability in Mendix SAML module. Limited detail on affected configurations and no information on known attacks or exploits. Organizations should verify SAML response signature validation in affected configurations and review Mendix SAML module versions.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.