CVE-2026-62220: Openclaw Auth Bypass Vulnerability

CVE-2026-62220 Overview

CVE-2026-62220 affects OpenClaw versions 2026.2.25 through 2026.5.25. The vulnerability allows a lower-trust caller or configured input path to bypass non-browser rate limits on WebSocket authentication attempts. When the affected feature is enabled and reachable from lower-trust input, attackers can consume gateway resources and reduce service availability. The flaw is tracked under CWE-307: Improper Restriction of Excessive Authentication Attempts.

Critical Impact
Attackers can bypass authentication rate limits on WebSocket endpoints, exhausting gateway resources and degrading availability for legitimate users.

Affected Products

OpenClaw versions 2026.2.25 through 2026.5.25 (Node.js distribution)
Deployments exposing WebSocket authentication to lower-trust input paths
Gateway components handling non-browser authentication requests

Discovery Timeline

2026-07-17 - CVE-2026-62220 published to the National Vulnerability Database
2026-07-21 - Last updated in NVD database

Technical Details for CVE-2026-62220

Vulnerability Analysis

OpenClaw enforces rate limits on WebSocket authentication attempts to prevent brute-force and resource-exhaustion attacks. The enforcement path treats browser and non-browser callers differently. Lower-trust callers can reach a configured input path that bypasses the non-browser rate limit check.

Once the limit is bypassed, an attacker can submit high volumes of authentication attempts against the WebSocket endpoint. The gateway allocates resources for each attempt, degrading availability for legitimate clients. The issue is a denial-of-service condition rooted in improper restriction of excessive authentication attempts [CWE-307].

Exploitation requires no authentication and no user interaction. The attack is network-reachable against any deployment where the affected feature is enabled and the input path is exposed.

Root Cause

The root cause is inconsistent rate-limit enforcement across authentication paths. The non-browser rate limiter is not applied to a configured input path reachable by lower-trust callers. As a result, the counter tracking failed or repeated authentication attempts is never incremented for requests traversing that path, and the throttling mechanism never triggers.

Attack Vector

The attack vector is network-based. An unauthenticated remote attacker sends WebSocket authentication requests through the input path that bypasses the non-browser rate limit. Repeated requests are processed without throttling, consuming CPU, memory, and connection slots on the gateway. See the GitHub Security Advisory GHSA-5p6w-wmh3-frfr and the VulnCheck Advisory for additional technical detail.

No public proof-of-concept exploit is available at the time of publication.

Detection Methods for CVE-2026-62220

Indicators of Compromise

Elevated volume of WebSocket authentication attempts from a single source IP or a narrow range of IPs
Repeated authentication failures against WebSocket endpoints without corresponding rate-limit responses
Sustained increases in gateway CPU, memory, or open connection counts without matching legitimate traffic growth
Non-browser User-Agent strings appearing in WebSocket handshake logs at unusual rates

Detection Strategies

Correlate WebSocket handshake logs with authentication outcome logs to identify sources exceeding expected attempt rates
Baseline normal authentication attempt volumes per client and alert on statistical outliers
Monitor for absence of rate-limit rejection responses (HTTP 429 or equivalent) alongside high request volumes

Monitoring Recommendations

Enable verbose logging on the OpenClaw gateway for WebSocket authentication endpoints
Forward gateway telemetry to a centralized log analytics platform for retention and correlation
Track resource utilization metrics on the gateway host and alert on sustained deviations from baseline

How to Mitigate CVE-2026-62220

Immediate Actions Required

Upgrade OpenClaw to version 2026.5.26 or later, which contains the fix
Inventory deployments to identify instances running versions 2026.2.25 through 2026.5.25
Restrict network exposure of WebSocket authentication endpoints to trusted sources until patching is complete

Patch Information

The vendor released a fix in OpenClaw 2026.5.26. Refer to the GitHub Security Advisory GHSA-5p6w-wmh3-frfr for release notes and upgrade guidance.

Workarounds

Place a reverse proxy or Web Application Firewall in front of the OpenClaw gateway and enforce rate limits at that layer
Restrict access to the affected input path via network ACLs or authenticated ingress controls
Disable the affected feature if it is not required by the deployment

bash

# Example: enforce a connection rate limit at the reverse proxy layer
# nginx snippet limiting WebSocket handshake requests per client IP
limit_req_zone $binary_remote_addr zone=ws_auth:10m rate=10r/m;

server {
    location /ws/auth {
        limit_req zone=ws_auth burst=5 nodelay;
        proxy_pass http://openclaw_backend;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
    }
}