Rust bip322 advisory discloses address-ownership verification bypass
A critical advisory identified an implementation flaw affecting proofs for native and wrapped SegWit key-hash addresses.
RustSec published advisory RUSTSEC-2026-0334 on October 9, 2026, identifying a critical ownership-verification bypass in the Rust bip322 crate. The issue affected P2WPKH and P2SH-P2WPKH address proofs.
Applications use ownership proofs to decide whether someone controls an address without requiring an ordinary payment. If a verifier accepts a proof that does not establish that control, an application can make a false authentication or authorization decision even though no Bitcoin consensus rule has changed.
The advisory concerned a particular software implementation. It was distinct from the later BIP322 clarification involving taproot upgrade mechanisms, which addressed interpretation of the specification itself.
The October disclosure made a concrete verification failure public. It did not establish that every BIP322 application was vulnerable, that users' private keys had leaked or that an attacker could spend arbitrary Bitcoin outputs merely by exploiting the proof checker.