Unverified certifier signatures persisted by acquire_certificate

Affected packages

Both bsv-sdk and bsv-wallet are published from the sgbett/bsv-ruby-sdk repository. The vulnerable code lives in lib/bsv/wallet_interface/wallet_client.rb, which is physically shipped inside both gems (the bsv-wallet.gemspec files list bundles the entire lib/bsv/wallet_interface/ tree). Consumers of either gem are independently vulnerable; the two packages are versioned separately, so each has its own affected range.

| Package | Affected | Patched | | --- | --- | --- | | bsv-sdk | >= 0.3.1, < 0.8.2 | 0.8.2 | | bsv-wallet | >= 0.1.2, < 0.3.4 | 0.3.4 |

Summary

BSV::Wallet::WalletClient#acquire_certificate persists certificate records to storage without verifying the certifier's signature over the certificate contents. Both acquisition paths are affected:

• acquisition_protocol: 'direct' — the caller supplies all certificate fields (including signature:) and the record is written to storage verbatim.
• acquisition_protocol: 'issuance' — the client POSTs to a certifier URL and writes whatever signature the response body contains, also without verification.

An attacker who can reach either API (or who controls a certifier endpoint targeted by the issuance path) can forge identity certificates that subsequently appear authentic to list_certificates and prove_certificate.

Details

BRC-52 requires a certificate's signature field to be verified against the claimed certifier's public key over a canonical hashing of (type, subject, serialNumber, revocationOutpoint, fields) before the certificate is trusted. The reference TypeScript SDK enforces this in Certificate.verify().

Direct path

The Ruby implementation's acquire_via_direct path (lib/bsv/wallet_interface/wallet_client.rb) constructs the certificate record directly from caller-supplied fields:

def...