CVE-2026-16119: GoClaw Auth Bypass Vulnerability

CVE-2026-16119 Overview

CVE-2026-16119 is an incorrect authorization vulnerability in nextlevelbuilder GoClaw versions up to 3.13.2. The flaw resides in the RequestApproval function within internal/tools/exec_approval.go, which handles the WebSocket Approval Endpoint. An authenticated remote attacker can manipulate approval requests to bypass authorization checks. A public exploit has been disclosed, increasing the likelihood of opportunistic abuse. The weakness is classified under CWE-285: Improper Authorization.

Critical Impact
Remote attackers with low privileges can bypass approval authorization in GoClaw, affecting confidentiality, integrity, and availability of protected operations exposed through the WebSocket Approval Endpoint.

Affected Products

nextlevelbuilder GoClaw versions up to and including 3.13.2
Component: WebSocket Approval Endpoint
File: internal/tools/exec_approval.go (RequestApproval function)

Discovery Timeline

2026-07-18 - CVE-2026-16119 published to NVD
2026-07-21 - Last updated in NVD database

Technical Details for CVE-2026-16119

Vulnerability Analysis

The vulnerability affects the approval workflow inside GoClaw, a Go-based tool that gates the execution of sensitive operations behind an approval mechanism. Approval requests traverse a WebSocket endpoint handled by the RequestApproval function in internal/tools/exec_approval.go. The function does not correctly enforce authorization on incoming requests. As a result, a low-privileged actor connected to the endpoint can influence approval decisions that should require higher privilege.

According to the disclosure, the exploit is public. That publication lowers the barrier to exploitation because attackers can reproduce the request flow without reversing the protocol.

Root Cause

The root cause is improper authorization checking within RequestApproval. The function accepts and processes WebSocket messages tied to approval decisions without validating that the requesting principal holds the privilege required for the requested action. This falls squarely under CWE-285: Improper Authorization, where an authentication step exists but the authorization enforcement is missing or incomplete.

Attack Vector

Exploitation occurs over the network against the WebSocket Approval Endpoint. The attacker must hold low-level privileges on the target instance, connect to the WebSocket channel, and issue crafted approval-related messages. No user interaction is required. Successful exploitation lets the attacker submit or influence approval outcomes that alter downstream execution logic. Technical reproduction details are documented in the GitHub Issue Discussion and the VulDB CVE Details entry.

No verified proof-of-concept code is reproduced here. Refer to the GitHub PoC Repository and the associated issue comment for exploitation details.

Detection Methods for CVE-2026-16119

Indicators of Compromise

Unexpected WebSocket connections to the GoClaw approval endpoint originating from low-privileged accounts or unusual source IPs.
Approval events in GoClaw logs that lack a corresponding legitimate operator action.
Execution of gated commands without a matching authorized approval record.

Detection Strategies

Correlate WebSocket session identifiers with the account privilege tier recorded in authentication logs to flag mismatches against approval outcomes.
Alert on repeated RequestApproval invocations from the same principal within short time windows, which may indicate probing.
Baseline normal approval patterns per user and detect deviations, particularly approvals granted outside working hours or without upstream request context.

Monitoring Recommendations

Enable verbose logging on the GoClaw WebSocket Approval Endpoint and forward events to a centralized SIEM for retention and correlation.
Monitor network egress and ingress to the GoClaw service for unauthorized clients establishing WebSocket sessions.
Track version inventory of GoClaw deployments to ensure vulnerable builds (<= 3.13.2) are visible to the security team.

How to Mitigate CVE-2026-16119

Immediate Actions Required

Restrict network access to the GoClaw WebSocket Approval Endpoint using firewall rules or reverse proxy allow-lists.
Reduce the number of accounts holding any level of access to GoClaw until a fixed release is deployed.
Review approval logs since the vulnerable version was deployed and revoke any suspicious approvals or downstream artifacts.

Patch Information

At the time of publication, no fixed release is referenced in the NVD entry. Track the upstream project at the GoClaw GitHub repository and the linked issue #1212 for a version above 3.13.2 that addresses the RequestApproval authorization check. Apply the patched release across all instances once published.

Workarounds

Place the GoClaw approval endpoint behind an authenticating reverse proxy that enforces role-based access control before requests reach RequestApproval.
Disable or gate the WebSocket Approval Endpoint at the network layer if the approval workflow is not currently required.
Rotate credentials and API tokens used with GoClaw to invalidate any that may have been captured by unauthorized clients.

bash

# Example: restrict access to the GoClaw WebSocket endpoint to a trusted subnet
iptables -A INPUT -p tcp --dport <goclaw_ws_port> -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport <goclaw_ws_port> -j DROP