CVE-2026-29613: OpenClaw Authentication Bypass Vulnerability

CVE-2026-29613 Overview

CVE-2026-29613 is an authentication bypass vulnerability in OpenClaw versions prior to 2026.2.12. The vulnerability exists in the BlueBubbles optional plugin webhook handler, which authenticates requests based solely on loopback remoteAddress without validating forwarding headers. This flawed authentication logic allows attackers to bypass configured webhook passwords when the OpenClaw gateway operates behind a reverse proxy, enabling unauthenticated remote attackers to inject arbitrary BlueBubbles message and reaction events by reaching the proxy endpoint.

Critical Impact

Unauthenticated remote attackers can bypass webhook authentication and inject arbitrary BlueBubbles message and reaction events when OpenClaw is deployed behind a reverse proxy, potentially leading to unauthorized data manipulation and service abuse.

Affected Products

• OpenClaw versions prior to 2026.2.12
• BlueBubbles plugin for OpenClaw (optional plugin)
• OpenClaw deployments behind reverse proxy configurations

Discovery Timeline

• 2026-03-05 - CVE-2026-29613 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-29613

Vulnerability Analysis

This authentication bypass vulnerability (CWE-306: Missing Authentication for Critical Function) stems from the BlueBubbles webhook handler's trust model for incoming requests. The handler incorrectly assumes that any request originating from a loopback address (127.0.0.1, ::1, or ::ffff:127.0.0.1) is inherently trusted and does not require password validation.

In modern deployment architectures where applications commonly operate behind reverse proxies (such as nginx, Apache, or cloud load balancers), all incoming requests appear to originate from the loopback interface since the proxy forwards them locally. The vulnerable code fails to account for this scenario by not validating standard forwarding headers like X-Forwarded-For or X-Real-IP, which would indicate the true origin of the request.

Root Cause

The root cause is the flawed authentication logic in the monitor.ts file within the BlueBubbles extension. The code checks if the request's remoteAddress matches loopback addresses and automatically grants access without requiring the configured webhook password. This design assumes loopback connections are always legitimate internal requests, which is incorrect when a reverse proxy is involved.

The vulnerable authentication check bypassed password verification entirely for any request that appeared to come from localhost, regardless of whether it was actually forwarded from an external source through a proxy.

Attack Vector

The attack vector is network-based and requires the target OpenClaw instance to be deployed behind a reverse proxy. An attacker can exploit this vulnerability by:

1. Identifying an OpenClaw instance with the BlueBubbles plugin enabled that operates behind a reverse proxy
2. Sending crafted HTTP requests to the webhook endpoint through the proxy
3. The proxy forwards the request to OpenClaw, and the request appears to originate from localhost
4. The vulnerable authentication logic trusts the loopback address and bypasses password validation
5. The attacker can then inject arbitrary BlueBubbles message and reaction events without authentication

The security patch removes the dangerous loopback trust logic and introduces timingSafeEqual for secure token comparison:

 import type { IncomingMessage, ServerResponse } from "node:http";
 import type { OpenClawConfig } from "openclaw/plugin-sdk";
+import { timingSafeEqual } from "node:crypto";
 import {
   normalizeWebhookMessage,
   normalizeWebhookReaction,

Source: GitHub Commit

The vulnerable loopback trust was removed entirely:

     if (guid && guid.trim() === token) {
       return true;
     }
-    const remote = req.socket?.remoteAddress ?? "";
-    if (remote === "127.0.0.1" || remote === "::1" || remote === "::ffff:127.0.0.1") {
-      return true;
-    }
     return false;
   });

Source: GitHub Commit

Detection Methods for CVE-2026-29613

Indicators of Compromise

• Unexpected BlueBubbles message or reaction events in OpenClaw logs without corresponding user actions
• Webhook endpoint access logs showing requests without valid authentication tokens
• Anomalous activity patterns in BlueBubbles message data indicating injection attempts
• Increased volume of requests to the BlueBubbles webhook endpoint from proxy-forwarded sources

Detection Strategies

• Monitor OpenClaw webhook endpoint logs for requests that lack proper authentication tokens but were processed successfully
• Implement application-level logging to track authentication bypass attempts on the BlueBubbles webhook handler
• Deploy network monitoring to detect unusual traffic patterns targeting the webhook endpoints
• Review proxy access logs for suspicious requests targeting OpenClaw webhook paths

Monitoring Recommendations

• Enable verbose logging on the BlueBubbles plugin to capture all webhook authentication attempts
• Configure alerting for failed and successful authentication events on webhook endpoints
• Implement rate limiting on webhook endpoints to detect and mitigate potential exploitation attempts
• Regularly audit BlueBubbles message and reaction data for signs of unauthorized injection

How to Mitigate CVE-2026-29613

Immediate Actions Required

• Upgrade OpenClaw to version 2026.2.12 or later immediately
• If immediate upgrade is not possible, disable the BlueBubbles plugin until patching is complete
• Review logs for any signs of prior exploitation or unauthorized webhook access
• Ensure webhook passwords are strong and properly configured

Patch Information

OpenClaw has released security patches addressing this vulnerability. The fixes are available in the following commits:

• Commit 743f4b28495cdeb0d5bf76f6ebf4af01f6a02e5a: Introduces timingSafeEqual for secure token comparison
• Commit f836c385ffc746cb954e8ee409f99d079bfdcd2f: Removes the vulnerable loopback address trust logic

For detailed patch information, refer to the GitHub Security Advisory and the VulnCheck Advisory.

Workarounds

• Disable the BlueBubbles plugin if not actively required in your deployment
• Implement additional network-level access controls to restrict webhook endpoint access
• Configure reverse proxy to add custom headers for internal authentication validation
• Deploy a Web Application Firewall (WAF) rule to validate webhook authentication at the proxy layer

# Example nginx configuration to add source IP header for validation
# Add to your OpenClaw reverse proxy configuration
location /webhook/bluebubbles {
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_pass http://localhost:3000;
}