Medium severity · published Oct 26, 2026
CVE-2026-89209
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…
New
6.8
CVSS
0.3%
EPSS
No
On KEV
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 compatible) (All versions < V3.6.29). Affected versions of the module do not properly protect against SAML assertion replay in IdP-initiated authentication flows. This could allow unauthenticated remote attackers to gain unauthorized access to the application by replaying a valid SAML response.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
Mendix SAML (Mendix 10 compatible) · Siemens
before V4.2.4 · source: vendor
MS
Mendix SAML (Mendix 11 compatible) · Siemens
before V4.2.4 · source: vendor
MS
Mendix SAML (Mendix 9 compatible) · Siemens
before V3.6.29 · source: vendor
Affected product
MS
Mendix SAML (Mendix 10 compatible)
Siemens
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89209
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-89209
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-137528.html
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