Shibboleth Plugin up to 2.5.3 on WordPress Identity Verification improper authentication

Summaryinfo

A vulnerability identified as critical has been detected in Shibboleth Plugin up to 2.5.3. The impacted element is an unknown function of the component Identity Verification. The manipulation leads to improper authentication. This vulnerability is traded as CVE-2026-12281. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Shibboleth Plugin up to 2.5.3. This issue affects some unknown functionality of the component Identity Verification. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Shibboleth WordPress plugin before 2.5.4 does not fail closed when its HTTP header identity mode is enabled without an anti-spoofing key, treating any request that carries identity headers as an authenticated session without verifying them. On a deployment where untrusted client headers reach the application, an unauthenticated attacker can log in with forged identity headers and, when automatic account creation and the default administrator role mapping are enabled, create and sign in as a new administrator. Exploitation requires the non-default HTTP header attribute mode, an empty or absent spoof key, automatic account creation enabled, and a deployment that does not strip untrusted client headers before they reach the application.

It is possible to read the advisory at wpscan.com. The identification of this vulnerability is CVE-2026-12281 since 06/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 2.5.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-44594). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• WordPress Plugin

Name

• Shibboleth Plugin

Version

• 2.5.0
• 2.5.1
• 2.5.2
• 2.5.3

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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