Description

ClawHub (the openclaw/clawhub application/backend) does not bind anonymous HTTP API requests to a trusted caller identity, so all direct anonymous API requests share a single default quota allowance. A remote, unauthenticated caller can drain that shared allowance and thereby deny or degrade API access for unrelated visitors. In addition, when the TRUST_FORWARDED_IPS option is enabled without an authenticated edge/proxy, clients can supply arbitrary forwarded IP headers to select quota identities of their choosing and evade rate limiting. The issue was confirmed at revision cbfee7343ddc867316dd9b3de6fa8856730f9f41; the complete historical affected range was not established. It is fixed in revision 8c2de6c506bb4efabe3f0c2ffb8370b9e23d4650 (PR #3684), where direct anonymous calls are redirected to the public API origin without consuming quota and forged identity assertions return HTTP 401. The npm CLI and OpenClaw runtime are separate products and are not affected.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.3",
  "pubDate": "2026-09-26T14:16:39.420Z",
  "pubdate": "2026-09-26T14:16:39.420Z",
  "executiveSummary": "ClawHub contains a vulnerability related to insufficient request identity verification and quota management. The system fails to properly isolate anonymous HTTP API requests, causing all unauthenticated traffic to share a single, global quota allowance. This flaw enables remote, unauthenticated attackers to perform resource exhaustion attacks, effectively triggering a Denial of Service (DoS) for legitimate users. Furthermore, when the TRUST_FORWARDED_IPS configuration is active without proper infrastructure controls, the application is susceptible to IP spoofing via arbitrary forwarded headers. This allows attackers to manipulate identity-based rate limiting, either by evading restrictions or by hijacking the quota identity of other visitors. The vulnerability impacts the ClawHub backend application, posing a significant risk to service availability and API integrity. Exploitation requires only network access to the API, requiring no specific credentials, making it a low-complexity attack vector that can be automated to degrade API performance globally.",
  "technicalDetails": "The core vulnerability in ClawHub resides in the backend API request handling logic, which fails to cryptographically bind anonymous requests to a unique, verified identity. Instead, the implementation aggregates all anonymous traffic into a single default quota bucket. This design flaw allows an attacker to exhaust the shared threshold by sending a high volume of requests, directly resulting in rate-limiting penalties for all other unauthenticated users.\nA secondary, critical issue exists in the processing of forwarded header information. When the TRUST_FORWARDED_IPS option is enabled, the application trusts headers such as X-Forwarded-For or similar mechanisms to determine the origin IP address for rate-limiting purposes. Because the application lacks a secure, authenticated proxy or edge configuration to strip or validate these headers, an attacker can supply malicious, arbitrary values in these headers. By crafting specific forwarded headers, an attacker can spoof the identity used by the quota management system.\nThe attack flow for resource exhaustion is straightforward: an attacker identifies the API endpoints governed by the shared anonymous quota. By initiating a burst of requests, the attacker triggers the backend rate-limiter, exhausting the quota and causing subsequent requests from both the attacker and legitimate users to be rejected with error responses. In the context of the spoofing vulnerability, the attack flow involves injecting falsified IP headers. The application logic utilizes these headers to index the quota bucket for the session. By rotating these injected headers, the attacker can effectively bypass any per-IP rate limits enforced by the system, allowing for sustained, high-frequency access that would otherwise be blocked.\nThe vulnerability was confirmed at revision cbfee7343ddc867316dd9b3de6fa8856730f9f41. The remediation, introduced in revision 8c2de6c506bb4efabe3f0c2ffb8370b9e23d4650 (PR #3684), fundamentally changes how anonymous requests are processed. Direct anonymous calls are now routed to a public API origin that does not consume quota, preventing the exhaustion of rate-limiting buckets. Additionally, the system now enforces stricter identity validation, returning HTTP 401 errors for requests where identity assertions appear forged or invalid."
}