{
  "cvss": 0.0,
  "datePublished": "2026-08-21T00:00:00Z",
  "dateUpdated": "2026-08-21T00:00:00Z",
  "description": "The SAML Single Sign On – SSO Login plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 5.4.4. This is due to the mo_saml_validate_signature() function performing a loose boolean check on the raw tri-state integer returned by PHP's openssl_verify(), causing an error return value of -1 to be evaluated as truthy and therefore treated as a successful signature verification. This makes it possible for unauthenticated attackers to log in as any existing WordPress user, including administrators, by submitting a crafted SAMLResponse containing an attacker-controlled NameID and a deliberately malformed signature value that triggers an OpenSSL processing error — bypassing verification entirely and resulting in wp_set_auth_cookie() being called for the targeted account.",
  "dueDate": "",
  "id": "CVE-2026-15981",
  "kev_catalogs": [
    "vulncheck"
  ],
  "knownRansomwareCampaignUse": "Unknown",
  "product": "saml_sp_single_sign_on",
  "requiredAction": "Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.",
  "severity": "HIGH",
  "source": "vulncheck_kev",
  "title": "MiniOrange saml_sp_single_sign_on Improper Authentication",
  "vendor": "MiniOrange"
}