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OpenclawApplication

CVE-2026-53840

HIGH · 7.1 CVSS v3.1 Published 2026-06-16
Fix available
A fix is available. Upgrade to 2026.5.12 or later.
See remediation →
77/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwards operator-configured custom headers during cross-origin redirects. Attackers controlling or compromising an MCP endpoint can redirect requests to exfiltrate sensitive headers like API keys or tenant-routing credentials to attacker-controlled origins.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

OpenClaw before version 2026.5.12 contains an information disclosure vulnerability where streamable-http MCP servers forward operator-configured custom headers during cross-origin redirects. Attackers who control or compromise an MCP endpoint can redirect requests to attacker-controlled origins, causing sensitive headers such as API keys and tenant-routing credentials to be exfiltrated.

MitigationUpgrade to OpenClaw version 2026.5.12 or later. Avoid placing sensitive credentials in custom headers that may be forwarded during cross-origin redirects until the patch is applied.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
OpenclawApplication
Affected:< 2026.5.12= 2026.5.12

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed OpenClaw version
    Check the version of the OpenClaw installation (e.g., via --version flag, package manager, or installed binaries)
    Affected if The installed version is earlier than 2026.5.12 or exactly 2026.5.12
  2. Confirm streamable-http MCP server is in use
    Determine whether the streamable-http MCP server component is enabled or configured in the OpenClaw deployment
    Affected if Streamable-http MCP server is actively used or configured
  3. Examine custom header configuration
    Review the MCP server configuration files or settings for any user-defined or operator-configured custom headers
    Affected if Custom headers are defined, particularly those containing API keys, tokens, tenant-routing credentials, or other sensitive authentication data
  4. Verify cross-origin redirect handling
    Inspect server logs or network traffic to observe whether cross-origin redirects occur during MCP server communication
    Affected if The server performs cross-origin redirects when handling MCP requests

A user is affected if they run any OpenClaw version before 2026.5.12 (or exactly 2026.5.12) with the streamable-http MCP server enabled and have sensitive credentials configured in custom headers that could be forwarded during cross-origin redirects.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2026.5.12 or later
Fixed in 2026.5.12
Interim mitigation

Upgrade to OpenClaw version 2026.5.12 or later. Avoid placing sensitive credentials in custom headers that may be forwarded during cross-origin redirects until the patch is applied.

Recommended fix Moderate confidence

OpenClaw 2026.5.12 or later stable release

  1. 1. Identify the currently installed OpenClaw version by checking the application manifest or version file
  2. 2. Back up all configuration files, especially any custom headers containing sensitive credentials (API keys, tenant-routing credentials)
  3. 3. Download the fixed release from the official OpenClaw repository (github.com)
  4. 4. Install the updated version following the standard upgrade procedure
  5. 5. After upgrade, verify that custom headers are no longer forwarded during cross-origin redirects by testing with a controlled redirect scenario
  6. 6. Rotate any credentials that may have been exposed, as the vulnerability may have been actively exploited
Caveat Review release notes for any breaking changes in the 2026.5.12 release before upgrading production systems

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Openclaw Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
25.0 hours of engineering $4,400
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,040.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-53840 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data