CVE-2026-75807: cyberlord92 saml single sign on – sso login Improper Authentication

Vulnerability summary

CVE-2026-75807 is a high (CVSS 7.5) Improper Authentication vulnerability in cyberlord92 saml single sign on – sso login. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 34% of scored vulnerabilities. Fixed in 5.4.7.

Timeline

1. 29-08-2026
   PublishedVulnerability first disclosed.
2. 31-08-2026
   Last modifiedVulnerability information updated.

Description

The SAML Single Sign On – SSO Login plugin for WordPress is vulnerable to Authentication Bypass in versions up to, and including, 5.4.6. This is due to the mo_saml_login_validate() ACS handler persisting the X.509 certificate extracted from an incoming SAMLResponse into the mo_saml_required_certificate option before the signature-validation verdict is enforced, because mo_saml_find_certificate() returns false on a fingerprint mismatch rather than halting execution. This makes it possible for unauthenticated attackers to overwrite the plugin's stored IdP signing certificate with an attacker-controlled value, and subsequently forge SAML assertions for any WordPress account — including administrators — to obtain a fully privileged session. Note: The exploit requires the administrator to perform a repair after receiving the test_config_error_wpsamlerr004 error message during the test configuration.

• CWE-287Improper AuthenticationWhen an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.