Vulnerability Description
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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Amazon | Tough | < 0.22.0 |
| Amazon | Tuftool | < 0.15.0 |
Related Weaknesses (CWE)
References
- https://aws.amazon.com/security/security-bulletins/2026-019-aws/Vendor Advisory
- https://crates.io/crates/tough/0.22.0Product
- https://crates.io/crates/tuftool/0.15.0Product
- https://github.com/awslabs/tough/releases/tag/tough-v0.22.0Release Notes
- https://github.com/awslabs/tough/releases/tag/tuftool-v0.15.0Release Notes
- https://github.com/awslabs/tough/security/advisories/GHSA-8m7c-8m39-rv4xVendor Advisory
FAQ
What is CVE-2026-6966?
CVE-2026-6966 is a vulnerability with a CVSS score of 5.3 (MEDIUM). 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 r...
How severe is CVE-2026-6966?
CVE-2026-6966 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-6966?
Check the references section above for vendor advisories and patch information. Affected products include: Amazon Tough, Amazon Tuftool.