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CVE-2026-53840

CVE-2026-53840 · OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 6.0 · Medium · EPSS 0.3% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • openclaw

    Versions
    • ≥ 0, < 2026.5.12: Affected (semver)
    • 2026.5.12: Not affected (semver)

    Update to 2026.5.12

  • openclaw npm

    Affected ranges
    • SEMVER: < 2026.5.12

    Update to 2026.5.12

Original sources

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