Critical Authentication Bypass Vulnerability in Siemens Mendix SAML Modules
In short: Siemens has identified an authentication bypass vulnerability in its Mendix SAML modules affecting versions compatible with Mendix 9, 10, and 11. An unauthenticated attacker can exploit this via a capture-replay attack on IdP-initiated authentication flows.
This summary was generated automatically by AI from CISA Advisories's publication. It is our own text, not a copy of the original — facts, figures and quotes belong to the source, linked above and below.
What changed?
- 1Fixed vulnerability CVE-2026-89209.
- 2Released Mendix SAML (Mendix 10/11) version 4.2.4.
- 3Released Mendix SAML (Mendix 9) version 3.6.29.
Why it matters
This vulnerability permits unauthorized access to applications relying on these modules. If your infrastructure uses Siemens Mendix components, this flaw could be exploited to hijack user sessions via captured SAML assertions.
What it means for AI agents and contact centers
Ensure your development and security teams verify if any internal or client-facing applications utilize the affected Mendix SAML modules. If used, apply the vendor patches immediately; as a temporary mitigation, disable IdP-initiated SSO.
Sources
- CISA AdvisoriesOfficialPrimary sourceOriginal article →„Siemens Mendix SAML Module“29 Oct 2026, 14:00Licence: US federal government work (17 U.S.C. §105) · our summary (content changed)
- Published by source
- 29 Oct 2026, 14:00
- Found by our system
- 29 Oct 2026, 17:22
- Summary generated
- 29 Oct 2026, 17:23
This article was written by AI from the original source. Facts, numbers and prices come from the source; missing values are marked “Not specified”. Legal notice, copyright and privacy