VulnerabilityDeferred

CVE-2026-75807

The SAML Single Sign On – SSO Login plugin for WordPress is vulnerable to Authentication Bypass in versions up to, and including, 5.4.6.

HIGH 7.5EPSS 0.29%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS: 0.29% probability · 21th percentile
CISA KEV: Not listed
Weakness: CWE-287
Source: security@wordfence.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.