GiveWP < 4.16.7.2 - Unauthenticated PHP Object Injection to RCE

Description

The plugin is vulnerable to PHP Object Injection via unsafe handling of serialized donor account data during the legacy donation process. An attacker without a pre-existing account can use the registration handler to create a donor account, store a serialized object in the account's last_name profile field, and cause the donation flow to preserve that object in the session. A subsequent request unserializes the session without restricting permitted classes. The plugin also contains a usable POP chain involving TCPDF and the ProviderForwarder trait that permits arbitrary operating-system command execution. On versions 4.16.6 through 4.16.7.1, exploitation additionally requires a publicly obtainable registration nonce and a legacy or option-based donation form; earlier affected releases are reachable with a published donation form and an active payment gateway.