How severe is CVE-2025-66017?

No CVSS score has been assigned to CVE-2025-66017 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-66017?

CVE-2025-66017 affects the following packages: cggmp21 (crates.io), cggmp24 (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2025-66017?

A fix is available for CVE-2025-66017; check the affected-versions list above or the advisory for the patched release of cggmp21, then make sure no transitive dependency still pins the vulnerable range.

How do I detect CVE-2025-66017 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cggmp21, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-66017 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2025-66017 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-66017 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-66017?

CVE-2025-66017 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 13th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-66017?

CVE-2025-66017 is classified as Broken Cryptographic Algorithm (CWE-327). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-66017 published, and has it been updated?

CVE-2025-66017 was published on November 25, 2025 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀 crates.io

Not in CISA KEV

CVE-2025-66017 — cggmp21

Fix: LFDT-Lockness/cggmp21@9d98157

CVE-2025-66017 is a Broken Cryptographic Algorithm vulnerability in cggmp21. A fix is available for cggmp21 — see the affected versions and patch details below.

CGGMP21 presignatures can be used in the way that significantly reduces security

Also known asGHSA-8frv-q972-9rq5RUSTSEC-2025-0127RUSTSEC-2025-0128

Published

Nov 25, 2025

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

1 / 2

Exploits

None indexed

Exploitation data as of Nov 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-66017.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs13th percentile — riskier than 13% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

2 pkgs affected

🦀cggmp21🦀cggmp24

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.

Description

Impact

This attack is against presignatures used in very specific context:

Presignatures + HD wallets derivation: security level reduces to 85 bits
Previously users could generate a presignature, and then choose a HD derivation path while issuing a partial signature via Presignature::set_derivation_path, which is malleable to attack that reduces target security level. To mitigate, this method has been removed from API.
Presignatures + "raw signing" (when signer signs a hash without knowing an original message): results into signature forgery attack
Previously, users were able to configure Presignature::issue_partial_signature with hashed message without ever providing original mesage. In new API, this method only accepts digests for which original message has been observed.

Patches

cggmp24 v0.7.0-alpha.2 release contains API changes that make it impossible to use presignatures in contexts in which it reduces security. Follow migration guidelines to upgrade.

Workarounds

Users can continue using un-patched versions of library as long as they don't use presignatures in said scenarios where it weakens system security. To be sure, migrate to patched version that excludes presignatures from being used in such scenarios.

References

Read this blog post to learn more.

Affected Packages

2 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`cggmp21`	all versions	No fix
🦀crates.io	`cggmp24`	all versions	0.7.0-alpha.2`cargo update -p cggmp24 --precise 0.7.0-alpha.2`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for cggmp21, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
A fix is available for CVE-2025-66017; check the affected-versions list above or the advisory for the patched release of cggmp21, then make sure no transitive dependency still pins the vulnerable range.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### Impact This attack is against presignatures used in very specific context: * Presignatures + HD wallets derivation: security level reduces to 85 bits \ Previously users could generate a presignature, and then choose a HD derivation path while issuing a partial signature via [`Presignature::set_derivation_path`](https://docs.rs/cggmp21/0.6.3/cggmp21/signing/struct.Presignature.html#method.set_derivation_path), which is malleable to attack that reduces target security level. To mitigate, this method has been removed from API. * Presignatures + "raw signing" (when signer signs a hash withou

O3 Security · Impact-Aware SCA

Is CVE-2025-66017 in your dependencies?

Find it across crates.io, including transitive dependencies.

Scan my dependencies How O3 SCA works