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

Source: https://junglewise.ai/threats/cve-2022-35961-openzeppelin-contracts-ecdsa-signature-malleability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-08-18. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2022-35961 · Severity: low · CVSS 3.1 · Published 2022-08-18

OpenZeppelin Contracts is a widely-used library for building secure blockchain applications. The library's ECDSA signature verification functions contain a flaw that allows an attacker to reuse signatures in different formats, potentially bypassing security controls that prevent replayed transactions. Applications relying on signature-based replay protection are at risk of unauthorized transaction replay attacks.

Technologies: [@openzeppelin/contracts (npm)](https://junglewise.ai/threats/technologies/openzeppelin-contracts), [@openzeppelin/contracts-upgradeable (npm)](https://junglewise.ai/threats/technologies/openzeppelin-contracts-upgradeable), [OpenZeppelin Contracts](https://junglewise.ai/threats/technologies/contracts), [OpenZeppelin Contracts Upgradeable](https://junglewise.ai/threats/technologies/contracts-upgradeable). Vendors: [npm](https://junglewise.ai/threats/vendors/npm), [OpenZeppelin](https://junglewise.ai/threats/vendors/openzeppelin).

## Quick answers

**Is CVE-2022-35961 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2022-35961 being exploited in the wild.

**How severe is CVE-2022-35961?** Low severity, with a CVSS score of 3.1, published 18 August 2022.

**Which products and versions are affected?** @openzeppelin/contracts (npm) SEMVER:introduced=4.1.0,fixed=4.7.3; @openzeppelin/contracts-upgradeable (npm) SEMVER:introduced=4.1.0,fixed=4.7.3; OpenZeppelin Contracts 4.1.0 to 4.7.2; OpenZeppelin Contracts Upgradeable 4.1.0 to 4.7.2.

**Is there a fix for CVE-2022-35961?** Yes. @openzeppelin/contracts (npm): upgrade to 4.7.3 or later; @openzeppelin/contracts-upgradeable (npm): upgrade to 4.7.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2022-35961 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2022-35961?** Check whether you run @openzeppelin/contracts (npm), @openzeppelin/contracts-upgradeable (npm), OpenZeppelin Contracts or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- @openzeppelin/contracts (npm): upgrade to 4.7.3 or later

  ```sh
  npm install @openzeppelin/contracts@4.7.3
  ```

- @openzeppelin/contracts-upgradeable (npm): upgrade to 4.7.3 or later

  ```sh
  npm install @openzeppelin/contracts-upgradeable@4.7.3
  ```


## Technical details

The ECDSA.recover and ECDSA.tryRecover functions (when taking a single bytes argument) accept both traditional 65-byte signatures and compact EIP-2098 64-byte encoded signatures, leading to signature malleability. Applications that implement replay or signature-reuse protection by marking the signature bytes as consumed—rather than the signed message or a nonce—are vulnerable to an attacker converting a previously-submitted signature to its compact form and resubmitting it to bypass this protection. The vulnerability only affects single-bytes variants; functions accepting r, v, s or r, vs as separate arguments are not affected. The patch in version 4.7.3 disables compact signature support in the single-bytes variant; compact signature support remains available via separate argument functions.

## Affected products

- OpenZeppelin @openzeppelin/contracts 4.1.0 to 4.7.2
- OpenZeppelin @openzeppelin/contracts-upgradeable 4.1.0 to 4.7.2

## Identifiers

- CVE-2022-35961
- GHSA-4h98-2769-gh6h

## Timeline

- 2022-08-18: disclosed: Security advisory published
- 2022-08-10: patched: Patch released in version 4.7.3

## References

- [https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-4h98-2769-gh6h](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/pull/3610)
- [https://github.com/OpenZeppelin/openzeppelin-contracts/commit/d693d89d99325f395182e4f547dbf5ff8e5c3c87](https://github.com/OpenZeppelin/openzeppelin-contracts/commit/d693d89d99325f395182e4f547dbf5ff8e5c3c87)
- [https://github.com/OpenZeppelin/openzeppelin-contracts](https://github.com/OpenZeppelin/openzeppelin-contracts)
- [https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v4.7.3](https://github.com/OpenZeppelin/openzeppelin-contracts/releases/tag/v4.7.3)

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