Missing Delegated Metadata Validation in awslabs/tough
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- Present
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-345.
Summary
Missing expiration, hash, and length enforcement in delegated metadata validation in awslabs/tough before tough-v0.22.0 allows remote authenticated users with delegated signing authority to bypass TUF specification integrity checks for delegated targets metadata and poison the local metadata cache, because load_delegations does not apply the same validation checks as the top-level targets metadata path. We recommend you upgrade to tough-v0.22.0 / tuftool-v0.15.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| AWS | tough | 0.9.0 – 0.21 | — | No fix listed | CNA |
| AWS | tuftool | up to 0.14 | — | No fix listed | CNA |
| — | tough (crates.io) | 0.9.0 to before 0.22.0 | 0.22.0 | Patch available | GHSA-4v58-8p28-2rq3 |
| — | tuftool (crates.io) | before 0.15.0 | 0.15.0 | Patch available | GHSA-4v58-8p28-2rq3 |
- tough VendorAWS Affected 0.9.0 – 0.21 Fixed in — No fix listed CNA
- tuftool VendorAWS Affected up to 0.14 Fixed in — No fix listed CNA
- tough (crates.io) Vendor— Affected 0.9.0 to before 0.22.0 Fixed in 0.22.0 Patch available GHSA-4v58-8p28-2rq3
- tuftool (crates.io) Vendor— Affected before 0.15.0 Fixed in 0.15.0 Patch available GHSA-4v58-8p28-2rq3
Remediation
- Fix · GHSA-4v58-8p28-2rq3 tough (crates.io) Fixed in 0.22.0 Advisory →
- Fix · GHSA-4v58-8p28-2rq3 tuftool (crates.io) Fixed in 0.15.0 Advisory →
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
AWS tough, tuftool — aws.amazon.com/security/security-bulletins/2026-019-aws
3 records Highest priority Priority LOW 3 LOW
Other records, highest priority first
- TI-2026-06100 Multiple Path Traversal Variants in awslabs/toughPriority LOW 32
- TI-2026-06098 Signature Threshold Bypass in awslabs/tough Delegated RolesPriority LOW 31
Timeline
- 2026-10-02 Threatist record created from CVE-2026-6967
- 2026-10-03 Alias added: GHSA-4v58-8p28-2rq3
- 2026-10-20 Affected versions changed · CNA
References
Patch 4
Advisory 3
More AWS Tough vulnerabilities
- TI-2020-11868 Improper verification of signature threshold in tough CVSS 3.1HIGH 8.6
- TI-2021-17989 Improper sanitization of delegated role names in tough CVSS 3.1HIGH 8.2
- TI-2021-17988 Improper sanitization of target names in tough CVSS 3.1HIGH 8.2
- TI-2026-06100 Multiple Path Traversal Variants in awslabs/tough CVSS 4.0HIGH 7.1
- TI-2026-06098 Signature Threshold Bypass in awslabs/tough Delegated Roles CVSS 4.0HIGH 7.0
- TI-2025-02523 Improper timestamp caching during snapshot rollback in tough CVSS 4.0MEDIUM 5.7
Sources
- CVE-2026-6967 · CVE Program
- CVE-2026-6967 · NVD
- FIRST EPSS
- GHSA-4v58-8p28-2rq3 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences