CVE-2023-23940 — OpenZeppelin Contracts for Cairo is a library for secure smart contract developm

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_

01What is this vulnerability?

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…

02Affected products

Vendor	Product	Versions
OpenZeppelin	cairo	contracts — >= 0.2.0, < 0.6.1

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-02-03T19:43:11.178Z
• Last modified: 2025-03-10T21:16:55.772Z

09References

• github.com — https://github.com/OpenZeppelin/cairo-contracts/security/advisories/GHSA-626q-v9…
• github.com — https://github.com/OpenZeppelin/cairo-contracts/pull/542/commits/6d4cb750478fca2…