CVE-2026-6966

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 v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-019-aws/	Vendor Advisory
https://crates.io/crates/tough/0.22.0	Product
https://crates.io/crates/tuftool/0.15.0	Product
https://github.com/awslabs/tough/releases/tag/tough-v0.22.0	Release Notes
https://github.com/awslabs/tough/releases/tag/tuftool-v0.15.0	Release Notes
https://github.com/awslabs/tough/security/advisories/GHSA-8m7c-8m39-rv4x	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:amazon:tough::::::rust::*
	cpe:2.3:a:amazon:tuftool::::::rust::*

History

No history.

Information

Published : 2026-04-24 20:16

Updated : 2026-06-17 11:01

NVD link : CVE-2026-6966

Mitre link : CVE-2026-6966

CVE.ORG link : CVE-2026-6966

JSON object : View

Products Affected

amazon

tough
tuftool

CWE

CWE-347

Improper Verification of Cryptographic Signature

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