cyberlord92 SAML Single Sign On Plugin up to 5.4.3 on WordPress SAML Signature Verification mo_saml_cast_key SignatureMethod weak password hash

Summaryinfo

A vulnerability identified as problematic has been detected in cyberlord92 SAML Single Sign On Plugin up to 5.4.3. This impacts the function mo_saml_cast_key of the component SAML Signature Verification. This manipulation of the argument SignatureMethod causes weak password hash. This vulnerability is registered as CVE-2026-15013. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in cyberlord92 SAML Single Sign On Plugin up to 5.4.3. It has been declared as problematic. Affected by this vulnerability is the function mo_saml_cast_key of the component SAML Signature Verification. The manipulation of the argument SignatureMethod with an unknown input leads to a weak password hash vulnerability. The CWE definition for the vulnerability is CWE-916. The product generates a hash for a password, but it uses a scheme that does not provide a sufficient level of computational effort that would make password cracking attacks infeasible or expensive. As an impact it is known to affect confidentiality. The summary by CVE is:

The SAML Single Sign On – SSO Login plugin for WordPress is vulnerable to Authentication Bypass via SAML Signature Algorithm Confusion in all versions up to, and including, 5.4.3. The vulnerability exists because `Mo_SAML_Utilities::mo_saml_cast_key()` reads the `SignatureMethod` Algorithm attribute directly from the attacker-controlled `SAMLResponse` parameter rather than enforcing the locally configured algorithm, causing the plugin to recast the IdP's RSA public key as an HMAC-SHA1 shared secret and validate the forged signature against it. This makes it possible for unauthenticated attackers to forge a SAML assertion targeting any WordPress account — including administrators — obtain valid WordPress authentication cookies, and achieve full administrator-level account takeover.

The advisory is shared at wordfence.com. This vulnerability is known as CVE-2026-15013 since 07/08/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1552 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• cyberlord92

Name

• SAML Single Sign On Plugin

Version

• 5.4.0
• 5.4.1
• 5.4.2
• 5.4.3

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion