CVE-2026-15013 json
SAML Single Sign On <= 5.4.3 - Unauthenticated Authentication Bypass via 'SAMLResponse' Parameter Signature Algorithm Confusion
published 2026-07-16 3 mo ago modified 2026-08-07 3 mo ago also EUVD-2026-44866
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.4%
- EPSS 2.4% chance of exploitation in 30 days, percentile 84%
- public exploits
- 1
- Exploit-DB
Summary
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.
Timeline
- Published
- First public exploit (EDB-52668)
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
2.45% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- EDB-52668 miniOrange 5.4.3 - Unauthenticated Auth Bypass webapps, 2026-09-01
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- cyberlord92 SAML Single Sign On – SSO Login
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/ee95092d-6351-4612-872d-284165bc1201?source=cve
- plugins.trac.wordpress.org /browser/miniorange-saml-20-single-sign-on/tags/5.4.3/class-mo-saml-utilities.php#L444
- plugins.trac.wordpress.org /browser/miniorange-saml-20-single-sign-on/tags/5.4.3/class-mo-saml-utilities.php#L416
- plugins.trac.wordpress.org /browser/miniorange-saml-20-single-sign-on/tags/5.4.3/class-mo-saml-utilities.php#L561
- plugins.trac.wordpress.org /browser/miniorange-saml-20-single-sign-on/tags/5.4.3/class-mo-saml-login-validate.php#L119
- plugins.trac.wordpress.org /browser/miniorange-saml-20-single-sign-on/tags/5.4.3/includes/lib/SAML2Core/class-mo-saml-xml-security-key.ph
- plugins.trac.wordpress.org /changeset?reponame=&old=3601345%40miniorange-saml-20-single-sign-on&new=3601345%40miniorange-saml-20-single-s
- seclists.org /fulldisclosure/2026/Aug/33
Sources
- CVE List CVE-2026-15013
- NVD CVE-2026-15013
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.