CVE-2026-6966

high

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.

References

https://aws.amazon.com/security/security-bulletins/2026-019-aws/

https://aws.amazon.com/security/security-bulletins/rss/2026-019-aws/

https://github.com/awslabs/tough/security/advisories/GHSA-8m7c-8m39-rv4x

https://github.com/awslabs/tough/releases/tag/tuftool-v0.15.0

https://github.com/awslabs/tough/releases/tag/tough-v0.22.0

https://crates.io/crates/tuftool/0.15.0

https://crates.io/crates/tough/0.22.0

Details

Source: Mitre, NVD

Published: 2026-04-24

Updated: 2026-05-06

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Severity: Medium

CVSS v4

Base Score: 7

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N

Severity: High

EPSS

EPSS: 0.00025