Metadata Integrity Vulnerability in Awslabs Tough Product
CVE-2026-6967

7.1HIGH

Key Information:

Vendor

Aws

Status
Tough
Tuftool
Vendor
CVE Published:
24 April 2026

What is CVE-2026-6967?

A vulnerability has been identified in the Awslabs Tough product, where missing expiration, hash, and length enforcement in delegated metadata validation allows remote authenticated users with delegated signing authority to bypass integral checks for metadata. This oversight could lead to poisoning the local metadata cache, as the load_delegations function does not enforce the same validation requirements as the top-level targets. To mitigate this risk, users are advised to upgrade to tough version 0.22.0 or tuftool version 0.15.0.

Affected Version(s)

tough 0.22.0

tuftool 0.15.0

References

https://aws.amazon.com/security/security-bulletins/2026-0...
vendor-advisory
https://github.com/awslabs/tough/releases/tag/tough-v0.22.0
patch
https://github.com/awslabs/tough/releases/tag/tuftool-v0....
patch

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.