Improper Verification of Cryptographic Signature
Rob Richards XmlSecLibs before 2.1.1 and 3.0.0 through 3.0.3, as used for example by SimpleSAMLphp, performed incorrect validation of cryptographic signatures in XML messages, allowing an authenticated attacker to impersonate others or elevate privileges by creating a crafted XML message.
CWE-347 - Improper Verification of Cryptographic Signature
A cryptographic protocol is meant to ensure that services are provided in a secure manner. An application with absent or improper verification of cryptographic signatures allows malicious users to feed false messages to valid users or to disclose sensitive data, subverting the goals of the protocol. This can lead to security failures such as false authentication, account hijacking, and privilege escalation.