Vulnerability · Published Jul 8, 2026 · Assigned by GitHub_M

CVE-2026-55874SeaweedFS: Path traversal in the S3 gateway X-Amz-Copy-Source header allows cross-bucket object read

High 7.7

In plain English

A high-severity path traversal in seaweedfs from seaweedfs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.7High

Exploit odds (30 days)0.6%top 50.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

SeaweedFS is a distributed storage system. Prior to 4.34, the S3 API gateway does not reject dot-dot path segments in the X-Amz-Copy-Source header used by CopyObject and UploadPartCopy, allowing an authenticated identity scoped to one bucket to read objects from other buckets through server-side copy. This issue is fixed in version 4.34.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/seaweedfs/seaweedfs	0.0.0-20260612000715-b44cf51fe931	GHSA-56wq-x3wv-3ff4
Go	github.com/seaweedfs/seaweedfs	0.0.0-20260612000715-b44cf51fe931	GO-2026-6327

Affected products (as reported)

Vendor	Product	Versions
seaweedfs	seaweedfs	< 4.34

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

References

https://github.com/seaweedfs/seaweedfs/security/advisories/GHSA-56wq-x3wv-3ff4 x_refsource_CONFIRM
https://github.com/seaweedfs/seaweedfs/pull/9929 x_refsource_MISC
https://github.com/seaweedfs/seaweedfs/commit/b44cf51fe931bd75aa4d37ae766bea90d7f85ccd x_refsource_MISC
https://github.com/seaweedfs/seaweedfs/releases/tag/4.34 x_refsource_MISC