CVE-2026-6966

EUVD-2026-25627
Improper verification of cryptographic signature uniqueness in delegated role validation in awslabs/tough before tough-v0.22.0 allows remote authenticated users to bypass the TUF signature threshold requirement by duplicating a valid signature, causing the client to accept forged delegated role metadata.

We recommend you upgrade to tough-v0.22.0 / tuftool-v0.15.0.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.3 MEDIUM
NETWORK
HIGH
LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://aws.amazon.com/security/security-bulletins/2026-019-aws/
https://crates.io/crates/tough/0.22.0
https://crates.io/crates/tuftool/0.15.0
https://github.com/awslabs/tough/releases/tag/tough-v0.22.0
https://github.com/awslabs/tough/releases/tag/tuftool-v0.15.0
https://github.com/awslabs/tough/security/advisories/GHSA-8m7c-8m39-rv4x