Description
NullHub through 2026.5.29 contains a missing authentication vulnerability that allows unauthenticated attackers to access the /api/* management API because the auth_token field defaults to null and is never assigned. Attackers sending requests without Authorization or Origin headers to non-loopback listeners can control agent instances, rewrite configurations including provider credentials, and manage cron jobs and MCP servers.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| nullclaw | NullHub | ≤ 2026.5.29 | — |
References
- https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/rJrLma3izg third-party-advisory
- https://github.com/nullclaw/nullhub/blob/v2026.5.29/src/server.zig#L546-L556 technical-description
- https://github.com/nullclaw/nullhub/blob/v2026.5.29/src/api/settings.zig#L29-L54 technical-description
- https://github.com/nullclaw/nullhub/blob/v2026.5.29/Dockerfile#L69-L71 technical-description
- https://github.com/nullclaw/nullhub product
- VulnCheck Advisory: NullHub through 2026.5.29 Missing Authentication for /api Management API third-party-advisory