Medium (5.3) in openzeppelin contracts. EPSS 0.2% chance of exploitation in the next 30 days. Fixed in openzeppelin-cairo-contracts 0.6.1.
OpenZeppelin Contracts for Cairo is a library for secure smart contract development written in Cairo for StarkNet, a decentralized ZK Rollup. `is_valid_eth_signature` is missing a call to `finalize_keccak` after calling `verify_eth_signature`. As a result, any contract using `is_valid_eth_signature` from the account library (such as the `EthAccount` preset) is vulnerable to a malicious sequencer. Specifically, the malicious sequencer would be able to bypass signature validation to impersonate an instance of these accounts. The issue has been patched in 0.6.1.
Severity
CVSS 3.1
5.3 medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
0.2% chance of exploitation in the next 30 days; higher than 12% of CVEs (scores of 2026-10-31)