cggmp21 has a missing check in the ZK proof used in CGGMP21

CVE-2025-66016 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Impact

cggmp21 concerns a missing check in the ZK proof that enables an attack in which a single malicious signer can reconstruct full private key.

Patches

  • cggmp21 v0.6.3 is a patch release that contains a fix that introduces this specific missing check
  • However, cggmp21 recommends upgrading to cggmp24 v0.7.0-alpha.2 which contains many other security checks as a precaution. Follow migration guideline to upgrade.

Workarounds

Update to cggmp21 v0.6.3, a minor release that contains a minimal security patch.

However, for full mitigation, users will need to upgrade to cggmp24 v0.7.0-alpha.2 as it contains many more security check implementations.

Resources

Read this blog post to learn more.

Basic information

Type
reviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-11-25 20:41:04 UTC
Updated
2025-11-27 08:59:49 UTC
GitHub reviewed
2025-11-25 20:41:04 UTC
NVD published
2025-11-25

EPSS Score

Score Percentile
0.04% 10.91%

CVSS Scores

Base score Version Severity Vector
9.3 4.0 —
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:H)
High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

Type Value
GHSA GHSA-m95p-425x-x889 ↗
CVE CVE-2025-66016 ↗

CWEs

CWE id Name
CWE-345 Insufficient Verification of Data Authenticity
CWE-347 Improper Verification of Cryptographic Signature

Affected packages (2)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
rust cggmp21 < 0.6.3 0.6.3 —
rust cggmp24 < 0.7.0-alpha.2 0.7.0-alpha.2 —

References

cvelogic Threat Intelligence