CVE-2018-7644: Simplesamlphp

High severity, CVSS 7.5. EPSS: 1.2% chance of exploitation in the next 30 days.

The XmlSecLibs library as used in the saml2 library in SimpleSAMLphp before 1.15.3 incorrectly verifies signatures on SAML assertions, allowing a remote attacker to construct a crafted SAML assertion on behalf of an Identity Provider that would pass as cryptographically valid, thereby allowing them to impersonate a user from that Identity Provider, aka a key confusion issue.

Affected products

• Simplesamlphp Simplesamlphp: before 1.15.3 (fixed in 1.15.3)

Published 2018-03-05. Last modified 2026-06-17.