CVE-2026-42439 Overview
CVE-2026-42439 is a Server-Side Request Forgery (SSRF) policy bypass vulnerability in OpenClaw versions prior to 2026.4.10. The flaw resides in the browser tabs action select and close routes exposed through the /tabs/action endpoint. Attackers with low-privilege access can bypass configured browser SSRF policy protections to perform unauthorized tab navigation operations. The issue is tracked under [CWE-862] (Missing Authorization) and [CWE-918] (Server-Side Request Forgery).
Critical Impact
Authenticated attackers can circumvent browser SSRF policy controls through the /tabs/action endpoint, enabling unauthorized tab navigation and access to subsequent system resources beyond the configured policy scope.
Affected Products
- OpenClaw (Node.js package) versions prior to 2026.4.10
- Deployments using browser tabs action select routes
- Deployments using browser tabs action close routes
Discovery Timeline
- 2026-05-05 - CVE-2026-42439 published to NVD
- 2026-05-07 - Last updated in NVD database
Technical Details for CVE-2026-42439
Vulnerability Analysis
OpenClaw exposes a /tabs/action endpoint that handles browser tab operations including selecting and closing tabs. The endpoint fails to apply the same SSRF policy enforcement used elsewhere in the application. As a result, attackers can issue tab navigation requests that reference destinations the SSRF policy is configured to block.
The vulnerability combines a missing authorization check [CWE-862] with an SSRF primitive [CWE-918]. While direct confidentiality and availability impact on the OpenClaw process itself is limited, the issue produces a high subsequent system impact because the controlled browser tab can interact with internal network resources, metadata services, or other targets shielded from direct external access.
Exploitation requires network reachability to the OpenClaw service and low-privilege authentication. No user interaction is required, and attack complexity is low.
Root Cause
The root cause is incomplete enforcement of the configured browser SSRF policy across all routes that trigger navigation. The select and close action routes under /tabs/action did not invoke the policy check applied to other navigation entry points, leaving a parallel code path that accepted attacker-controlled targets without validation.
Attack Vector
An authenticated attacker sends a crafted request to the /tabs/action endpoint specifying a tab action (select or close) with a destination that the SSRF policy would normally reject. Because the policy gate is missing on these routes, the action is processed and the controlled browser tab navigates to the attacker-supplied target. The vulnerability mechanism is documented in the VulnCheck SSRF Advisory and addressed in the upstream commit.
Detection Methods for CVE-2026-42439
Indicators of Compromise
- Unexpected HTTP requests to the /tabs/action endpoint from authenticated low-privilege accounts.
- Browser tab navigation events targeting internal IP ranges, link-local addresses (169.254.169.254), or loopback destinations.
- Repeated tab select or close actions referencing hosts that should be blocked by the configured SSRF policy.
Detection Strategies
- Inspect application access logs for POST or GET requests to /tabs/action and correlate target URLs against the SSRF allow list.
- Alert on tab action requests where the resolved destination falls within RFC1918, loopback, or cloud metadata ranges.
- Compare requests reaching /tabs/action against the policy decisions logged for other navigation routes to surface bypassed paths.
Monitoring Recommendations
- Forward OpenClaw application and reverse-proxy logs to a centralized analytics platform for correlation with egress network telemetry.
- Monitor outbound traffic from the OpenClaw host for connections to internal services that should be unreachable from the application tier.
- Track the deployed OpenClaw version against 2026.4.10 and flag instances running earlier releases.
How to Mitigate CVE-2026-42439
Immediate Actions Required
- Upgrade OpenClaw to version 2026.4.10 or later, which includes the fix from commit 48c0347921b7e9438af0312968fc360ca88023f3.
- Restrict access to the /tabs/action endpoint to trusted users and networks until the upgrade is applied.
- Audit existing accounts and revoke unnecessary low-privilege access that could reach the vulnerable routes.
Patch Information
The fix is shipped in OpenClaw 2026.4.10. Vendor details are available in the GitHub Security Advisory GHSA-rj2p-j66c-mgqh and the corresponding code commit. Apply the upgrade through your standard Node.js package management workflow and redeploy affected services.
Workarounds
- Block or filter requests to /tabs/action at an upstream reverse proxy or web application firewall until patching is complete.
- Enforce egress network controls that prevent the OpenClaw process from reaching internal-only or metadata endpoints regardless of application-layer policy.
- Disable the browser tabs action functionality in deployments that do not require it.
# Upgrade OpenClaw to the patched release
npm install openclaw@2026.4.10
# Verify the installed version
npm list openclaw
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
