# CVE-2025-66016: RUSTSEC-2025-0130 - Missing check in ZK proof in CGGMP21 Threshold Signing Protocol

Source: https://junglewise.ai/threats/cve-2025-66016-cggmp21-has-a-missing-check-in-the-zk-proof-used-in-cggmp21  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-11-25  
License: CC BY 4.0 with a link back

CVE-2025-66016 · Severity: medium · CVSS 4 · Published 2025-11-25

CGGMP24 is a state-of-art ECDSA TSS protocol that supports 1-round signing (requires 3 preprocessing rounds), identifiable abort, and a key refresh protocol. Prior to version 0.6.3, there is a missing check in the ZK proof that enables an attack in which single malicious signer can reconstruct full private key. This issue has been patched in version 0.6.3, for full mitigation it is recommended to upgrade to cggmp24 version 0.7.0-alpha.2 as it contains more security checks.

Technologies: [cggmp21 (crates.io)](https://junglewise.ai/threats/technologies/cggmp21). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is CVE-2025-66016 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-66016 being exploited in the wild.

**How severe is CVE-2025-66016?** Medium severity, with a CVSS score of 4, published 25 November 2025.

**Which products and versions are affected?** cggmp21 (crates.io) SEMVER:introduced=0,fixed=0.6.3, SEMVER:introduced=0.0.0-0,fixed=0.6.3; cggmp24 (crates.io) SEMVER:introduced=0,fixed=0.7.0-alpha.2, SEMVER:introduced=0.0.0-0,fixed=0.7.0-alpha.2.

**Is there a fix for CVE-2025-66016?** Yes. cggmp21 (crates.io): upgrade to 0.6.3 or later; cggmp24 (crates.io): upgrade to 0.7.0-alpha.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-66016?** Check whether you run cggmp21 (crates.io) or cggmp24 (crates.io) 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

- cggmp21 (crates.io): upgrade to 0.6.3 or later

  ```sh
  cargo update -p cggmp21
  ```

- cggmp24 (crates.io): upgrade to 0.7.0-alpha.2 or later

  ```sh
  cargo update -p cggmp24
  ```


## Affected products

- cggmp21 (crates.io) SEMVER:introduced=0,fixed=0.6.3, SEMVER:introduced=0.0.0-0,fixed=0.6.3
- cggmp24 (crates.io) SEMVER:introduced=0,fixed=0.7.0-alpha.2, SEMVER:introduced=0.0.0-0,fixed=0.7.0-alpha.2

## Identifiers

- CVE-2025-66016
- GHSA-m95p-425x-x889
- RUSTSEC-2025-0129
- RUSTSEC-2025-0130

## Related threats

- [RUSTSEC-2025-0127 - CGGMP21 presignatures can be used in the way that significantly reduces security](https://junglewise.ai/threats/cve-2025-66017-cggmp24-and-cggmp21-are-vulnerable-to-signature-forgery-through)
- [cggmp21 vulnerable to ambiguous challenge derivation](https://junglewise.ai/threats/cggmp21-vulnerable-to-ambiguous-challenge-derivation-76290254)
- [RUSTSEC-2024-0393 - Ambiguous challenge derivation](https://junglewise.ai/threats/rustsec-2024-0393-ambiguous-challenge-derivation-656c2a00)