Is CVE-2026-72921 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-72921 being exploited in the wild.

How severe is CVE-2026-72921?

High severity, with a CVSS score of 8.1, published 2 September 2026.

Which products and versions are affected?

github.com/seaweedfs/seaweedfs (Go) < 0.0.0-20260512171048-05ed5c9ae8a2, SEMVER:introduced=0,fixed=0.0.0-20260512171048-05ed5c9ae8a2.

Is there a fix for CVE-2026-72921?

Yes. github.com/seaweedfs/seaweedfs (Go): upgrade to 0.0.0-20260512171048-05ed5c9ae8a2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-72921 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-72921?

Check whether you run github.com/seaweedfs/seaweedfs (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-72921: SeaweedFS Filer JWT authorization bypass in allowed_prefixes

Q: Is there a fix for CVE-2026-72921?

Yes. github.com/seaweedfs/seaweedfs (Go): upgrade to 0.0.0-20260512171048-05ed5c9ae8a2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-72921 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-72921?

Check whether you run github.com/seaweedfs/seaweedfs (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-72921 · Severity: high · CVSS 8.1 · Published 2026-09-02

SeaweedFS is a distributed storage system used to store and manage files across multiple servers in multi-tenant environments. A flaw in its JWT-based path authorization allows a token scoped to one tenant path (e.g., `/tenant1`) to also access sibling paths with similar names (e.g., `/tenant1234`, `/tenant1-old`). This enables unauthorized cross-tenant data access for both reading and writing, affecting the confidentiality and integrity of isolated tenant data.

Technologies: github.com/seaweedfs/seaweedfs (Go). Vendors: Go.

Quick answers

Is CVE-2026-72921 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-72921 being exploited in the wild.
How severe is CVE-2026-72921?: High severity, with a CVSS score of 8.1, published 2 September 2026.
Which products and versions are affected?: github.com/seaweedfs/seaweedfs (Go) < 0.0.0-20260512171048-05ed5c9ae8a2, SEMVER:introduced=0,fixed=0.0.0-20260512171048-05ed5c9ae8a2.
Is there a fix for CVE-2026-72921?: Yes. github.com/seaweedfs/seaweedfs (Go): upgrade to 0.0.0-20260512171048-05ed5c9ae8a2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-72921 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-72921?: Check whether you run github.com/seaweedfs/seaweedfs (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/seaweedfs/seaweedfs (Go): upgrade to 0.0.0-20260512171048-05ed5c9ae8a2 or later
```
go get github.com/seaweedfs/seaweedfs@v0.0.0-20260512171048-05ed5c9ae8a2
```

Technical details

The vulnerability is a path traversal / authorization bypass in SeaweedFS Filer's JWT validation logic. The affected component `weed/server/filer_server_handlers.go` uses `strings.HasPrefix()` for a literal byte-prefix match when validating tokens against the `allowed_prefixes` configuration. This means a token authorized for `/tenant1` will incorrectly match paths like `/tenant1234`, `/tenant1-old`, and `/tenant1backup`. The attack requires a valid, legitimately-issued JWT scoped to a tenant; an attacker cannot forge tokens. Once in possession of a scoped token, the holder can read and write to unintended tenant directories. The fix, available in version 4.24 and later, normalizes paths with `path.Clean()` and matches on `/`-separated path components, ensuring `/tenant1` only authorizes `/tenant1` and its true descendants.

Affected products

SeaweedFS SeaweedFS < 4.24

Identifiers

CVE-2026-72921
GHSA-gv5w-hfx8-8cwq
GO-2026-6361

Timeline

2026-07-08: disclosed
2026-09-02: advisory: GitHub Advisory published
2026-04-12: patched: Fixed in version 4.24

References

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