OpenZeppelin Contracts vulnerable to ECDSA signature malleability

Impact

The functions ECDSA.recover and ECDSA.tryRecover are vulnerable to a kind of signature malleability due to accepting EIP-2098 compact signatures in addition to the traditional 65 byte signature format. This is only an issue for the functions that take a single bytes argument, and not the functions that take r, v, s or r, vs as separate arguments.

The potentially affected contracts are those that implement signature reuse or replay protection by marking the signature itself as used rather than the signed message or a nonce included in it. A user may take a signature that has already been submitted, submit it again in a different form, and bypass this protection.

Patches

The issue has been patched in 4.7.3.

For more information

If you have any questions or comments about this advisory, or need assistance deploying a fix, email us at [email protected].