CVE-2026-53859: OpenClaw hostname validation bypass in model and workspace URLs

CVE-2026-53859 · Severity: medium · CVSS 6.5 · Published 2026-06-16

OpenClaw, a tool used for managing workspace and model-derived URLs, contains a flaw in how it validates web addresses. An attacker could bypass security filters by adding a trailing dot to a restricted web address, potentially allowing them to access internal or private network resources that should be blocked. This could lead to the exposure of sensitive internal data or metadata.

Technologies: openclaw (npm), Openclaw. Vendors: npm, Openclaw.

Quick answers

Is CVE-2026-53859 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-53859 being exploited in the wild.
How severe is CVE-2026-53859?
Medium severity, with a CVSS score of 6.5, published 16 June 2026.
Which products and versions are affected?
openclaw (npm) SEMVER:introduced=0,fixed=2026.5.26; Openclaw <= 2026.5.22, before 2026.5.26.
Is there a fix for CVE-2026-53859?
Yes. openclaw (npm): upgrade to 2026.5.26 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-53859 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-53859?
Check whether you run openclaw (npm) or Openclaw at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • openclaw (npm): upgrade to 2026.5.26 or later
    npm install openclaw@2026.5.26

Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in OpenClaw due to improper input validation of hostnames. The application's hostname blocklist check fails to account for trailing dots (e.g., 'example.com.'), treating them differently than the standard hostname ('example.com'). An authenticated attacker with low privileges can provide a crafted URL containing a trailing dot to bypass security policies and reach restricted internal network destinations or metadata services. The issue is fixed in version 2026.5.26.

Affected products

  • openclaw openclaw <= 2026.5.22

Identifiers

  • CVE-2026-53859
  • GHSA-gxg4-2rrr-jhc7

Timeline

  • 2026-05-28: disclosed
  • 2026-05-28: advisory: Initial GitHub advisory published
  • 2026-06-18: patched: First stable patched version 2026.5.26 confirmed

References

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