GHSA-4v58-8p28-2rq3 — tough
MEDIUMGHSA-4v58-8p28-2rq3 is a medium-severity (CVSS 5.9) CWE-345 vulnerability in tough. A fix is available for tough — see the affected versions and patch details below.
awslabs/tough is Missing Delegated Metadata Validation
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-4v58-8p28-2rq3.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-4v58-8p28-2rq3 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
tough🦀tuftoolReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
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.
Impact
The tough library, prior to 0.22.0, does not properly verify delegated target metadata. It allows someone with write access to the metadata to serve expired or otherwise invalid targets from a TUF repository which tough will then trust rather than reject.
Impacted Versions:
tough 0.9.0 through 0.21.x, tuftool through 0.14.x
Patches
This issue has been addressed in tough version 0.22.0 and tuftool version 0.15.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.
Workarounds
No workarounds to this issue are known.
References
- CVE-2026-6967 If there are any questions or comments about this advisory, please contact [AWS/Amazon] Security via the vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
Amazon Web Services Labs would like to thank Oleh Konko of 1seal for collaborating on this issue through the coordinated vulnerability disclosure process.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | tough | ≥ 0.9.0&&< 0.22.0 | 0.22.0cargo update -p tough --precise 0.22.0 |
| 🦀crates.io | tuftool | all versions | 0.15.0cargo update -p tuftool --precise 0.15.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tough, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update tough to 0.22.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4v58-8p28-2rq3 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-4v58-8p28-2rq3 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-4v58-8p28-2rq3. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4v58-8p28-2rq3 in your dependencies?
O3 Security finds GHSA-4v58-8p28-2rq3 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.