CVE-2025-40758: Siemens Mendix SAML (Mendix 10.12 compatible) · Improper Verification of Cryptographic Signature
Affects Siemens Mendix SAML (Mendix 10.12 compatible)Source CVE Database V5
Not known to be exploited · CVSS 8.7 High.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 14% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 14 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Siemens Mendix SAML (Mendix 10.12 compatible) | Affected
| Fixed in– |
AI-suggested
European organizations should immediately assess their use of Mendix SAML modules and identify affected versions. The primary mitigation is to upgrade affected Mendix SAML modules to the fixed versions: V4.0.3 or later for Mendix 10.12 compatible, V4.1.2 or later for Mendix 10.21 compatible, and V3.6.21 or later for Mendix 9.24 compatible. Where immediate upgrade is not feasible, organizations should implement compensating controls such as: 1) Enforce strict SAML binding and signature validation policies at the identity provider (IdP) and service provider (SP) levels to detect and reject malformed or unsigned assertions. 2) Monitor authentication logs for anomalous SSO activity indicative of signature bypass attempts. 3) Employ multi-factor authentication (MFA) as an additional layer to reduce the risk of account compromise. 4) Conduct thorough security reviews of SAML configurations to ensure adherence to best practices, including validating all SAML responses and requests. 5) Limit the exposure of SAML endpoints to trusted networks and implement network segmentation to reduce attack surface. 6) Stay updated with Siemens security advisories and apply patches promptly. These targeted actions go beyond generic advice by focusing on the specific cryptographic signature verification weakness and SSO context.
Description
A vulnerability has been identified in Mendix SAML (Mendix 10.12 compatible) (All versions < V4.0.3), Mendix SAML (Mendix 10.21 compatible) (All versions < V4.1.2), Mendix SAML (Mendix 9.24 compatible) (All versions < V3.6.21). Affected versions of the module insufficiently enforce signature validation and binding checks. This could allow unauthenticated remote attackers to hijack an account in specific SSO configurations.