CVE-2026-77998

CVE-2026-77998 is a critical-severity vulnerability rated 10/10 on the CVSS scale. Joomla Extension - miniorange.com - Unauthenticated Authentication Bypass via SAMLResponse Parameter in miniOrange SAML SSO < 11.0.2, SAML SP Single Sign On – Login with ADFS < 6.4, SAML SP Single Sign On – SAML SSO login with Google Apps < 6.4 - 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 Joomla 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.. EPSS estimates a 0.34% chance of exploitation in the next 30 days.