GHSA-56wq-x3wv-3ff4 is a high-severity (CVSS 7.7) Path Traversal vulnerability in github.com/seaweedfs/seaweedfs. O3 Security confirms whether GHSA-56wq-x3wv-3ff4 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SeaweedFS: Path traversal in the S3 gateway X-Amz-Copy-Source header allows cross-bucket object read
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-56wq-x3wv-3ff4.
Real-World Exposure
github.com/seaweedfs/seaweedfsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The SeaweedFS S3 API gateway did not reject .. path segments in the X-Amz-Copy-Source header used by CopyObject and UploadPartCopy. The request URL path was hardened against traversal in 4.30 (CVE-2026-54917), but the copy-source header was only checked for emptiness, so a .. segment in the copy source survived into the server-side filer path and resolved into a different bucket.
Impact
A confused-deputy authorization bypass that breaks bucket isolation. IAM evaluates the caller's policy against the bucket named in the request URL (the destination the caller owns), while the copy reads its source from the traversed target bucket. An identity scoped to a single bucket (Read + Write on one bucket it controls) can therefore read any object in any bucket on the instance and land the result in its own bucket.
For example, a caller authorized only for bucket-a issues a CopyObject into bucket-a with copy source bucket-a/../<victim-bucket>/<key>; the gateway reads <victim-bucket>/<key> and writes it to the attacker-controlled destination, from which the caller reads it normally. UploadPartCopy (CopyObjectPartHandler) is affected by the same vector.
Affected versions
All releases prior to 4.34. The 4.30 fix for CVE-2026-54917 hardened the request URL path but not the X-Amz-Copy-Source header.
Patched version
4.34 and later.
Remediation
Upgrade to 4.34 or later. The fix validates the copy-source bucket and object key with the same IsValidBucketName / IsValidObjectKey guards already applied to the request URL, rejecting traversal segments before the handler runs, and applies the same check to UploadPartCopy.
Workaround
No configuration workaround. For deployments that cannot upgrade immediately, front the gateway with a reverse proxy that rejects requests whose X-Amz-Copy-Source header contains .., %2e%2e, or backslash sequences.
References
- Fix: https://github.com/seaweedfs/seaweedfs/pull/9929 (commit b44cf51fe931bd75aa4d37ae766bea90d7f85ccd)
Credit
Reported responsibly by @47Cid.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/seaweedfs/seaweedfs | all versions | 0.0.0-20260612000715-b44cf51fe931 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/seaweedfs/seaweedfs. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/seaweedfs/seaweedfs to 0.0.0-20260612000715-b44cf51fe931 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-56wq-x3wv-3ff4 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 pinpoints whether GHSA-56wq-x3wv-3ff4 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-56wq-x3wv-3ff4. 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-56wq-x3wv-3ff4 in your dependencies?
O3 detects GHSA-56wq-x3wv-3ff4 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.