GHSA-r7vq-6425-j94w — tuf
Fix: theupdateframework/python-tuf#1218GHSA-r7vq-6425-j94w is a security vulnerability in tuf. A fix is available for tuf — see the affected versions and patch details below.
Python-TUF vulnerable to incorrect threshold signature computation for new root metadata
Real-World Exposure
tufReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The function _verify_root_self_signed(), introduced in v0.14.0, and which verifies self-signatures in a new root metadata file, counted multiple signatures by any new root key towards the new threshold. That is, any single new root key could theoretically provide enough signatures to meet the threshold for new key self-signatures required during root metadata update.
A scenario where this attack could be relevant is amazingly unlikely in practice to the point where labeling this issue as a security advisory is potentially overstating the impact of the issue. Given that new root keys only become trusted by the client after a successful root metadata update, which also requires the quorum of signatures from old trusted root keys, this issue has been evaluated as low in severity.
In particular, in order to exploit this vulnerability, an attacker must:
- Control one new root key.
- Craft a new root metadata file such that there is a number of signatures by this new root key greater than or equal to the new threshold.
- Cause a valid threshold of the old root keys to sign this new root metadata file.
- Cause this new root metadata file to be published on the repository.
- Cause clients to rotate to this new root metadata file.
Patches
A fix is available since version 0.16.0.
Workarounds
No workarounds are known for this issue.
References
- Pull request resolving the issue PR 1218
- Pull request which introduced the faulty computation of signature threshold on new root metadata PR 1101
- A similar previous issue with incorrectly computed signature thresholds in tuf is described in GHSA-pwqf-9h7j-7mv8
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | tuf | ≥ 0.14.0&&< 0.16.0 | 0.16.0pip install --upgrade 'tuf==0.16.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tuf, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update tuf to 0.16.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r7vq-6425-j94w 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-r7vq-6425-j94w can be triaged on real exposure rather than presence alone.
Tailored to GHSA-r7vq-6425-j94w. 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-r7vq-6425-j94w in your dependencies?
O3 Security finds GHSA-r7vq-6425-j94w across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.