Buffa is a pure-Rust Protocol Buffers implementation with first-class protobuf editions support. Prior to 0.7.0, a soundness bug in the OwnedView<V> type allowed safe Rust code to trigger a use-after-free: the OwnedView::decode constructor transmuted a borrowed slice to &'static [u8], and the Deref implementation exposed the promoted 'static lifetime on borrowed view fields (such as &'static str and &'static [u8]) to callers, so the borrow checker permitted those references to outlive the OwnedView; once the OwnedView was dropped and its backing buffer freed, the references became dangling, enabling memory corruption, information disclosure of freed heap contents, and cross-thread misuse without any unsafe code in the calling application. This issue is fixed in version 0.7.0.

Affected: crates.io: buffa

A soundness bug in `buffa`'s `OwnedView<V>` allowed safe Rust code to trigger a use-after-free. The `OwnedView::decode` constructor transmuted a borrowed slice to `&'static [u8]`, and the `Deref` implementation exposed the promoted `'static` lifetime on borrowed view fields (such as `&'static str` and `&'static [u8]`) to callers. Because these references appeared to be `'static`, the borrow checker permitted them to outlive the `OwnedView`; once the `OwnedView` was dropped and its backing buffer freed, those references became dangling, enabling memory corruption, information disclosure of freed heap contents, and cross-thread misuse — all without any `unsafe` code in the calling application. Users are advised to update to the latest patched version of buffa.

Thank you to hackerone.com/suul for reporting this issue.