CVE-2026-53840

HIGHPre-NVD 7.17.1—
EchelonGraph scoreHIGH confidence

Score 7.1 from GitHub Security Advisory published 2026-06-16. a secondary CVSS source baseline 7.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
7.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.1Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
7.1
EG Score
7.1(high)
EPSS
12.9%
KEV
Not listed

Published

June 16, 2026

Last Modified

June 17, 2026

Advisory Details (2)

Auto-updated Jun 16, 2026
Patch available. Sources: github.
generic

OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects | Advisories | VulnCheck

https://www.vulncheck.com/advisories/openclaw-custom-header-leakage-via-mcp-streamable-http-cross-origin-redirects
github Patch Available

MCP Streamable HTTP redirects could forward configured custom headers to another origin · Advisory · openclaw/openclaw · GitHub

https://github.com/openclaw/openclaw/security/advisories/GHSA-rjxq-qqhf-8hwh

Vendor Advisories for CVE-2026-53840(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
openclaw—2026.5.12—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 21× in last 7d / 71× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-06 23:07 UTCEG score recompute
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-05 22:43 UTCEG score recompute
  7. 2026-07-05 10:17 UTCEG score recompute
  8. 2026-07-05 02:31 UTCEPSS rescore
  9. 2026-07-05 02:30 UTCEPSS rescore
  10. 2026-07-04 21:35 UTCEG score recompute
  11. 2026-07-04 09:08 UTCEG score recompute
  12. 2026-07-04 06:31 UTCEPSS rescore
  13. 2026-07-04 06:31 UTCEPSS rescore
  14. 2026-07-03 13:47 UTCEG score recompute
  15. 2026-07-02 22:30 UTCEG score recompute
  16. 2026-07-02 10:05 UTCEG score recompute
  17. 2026-07-01 21:38 UTCEG score recompute
  18. 2026-07-01 15:07 UTCEPSS rescore
  19. 2026-07-01 09:10 UTCEG score recompute
  20. 2026-06-30 23:22 UTCEPSS rescore
  21. 2026-06-30 20:44 UTCEG score recompute
  22. 2026-06-30 08:10 UTCEG score recompute
  23. 2026-06-29 19:44 UTCEG score recompute
  24. 2026-06-29 14:06 UTCEPSS rescore
  25. 2026-06-29 14:06 UTCEPSS rescore
Show 46 more
  1. 2026-06-29 07:18 UTCEG score recompute
  2. 2026-06-28 18:52 UTCEG score recompute
  3. 2026-06-28 14:07 UTCEPSS rescore
  4. 2026-06-28 06:26 UTCEG score recompute
  5. 2026-06-28 04:56 UTCEPSS rescore
  6. 2026-06-28 04:56 UTCEPSS rescore
  7. 2026-06-27 17:57 UTCEG score recompute
  8. 2026-06-27 05:29 UTCEG score recompute
  9. 2026-06-27 03:08 UTCEPSS rescore
  10. 2026-06-26 17:04 UTCEG score recompute
  11. 2026-06-26 04:39 UTCEG score recompute
  12. 2026-06-25 16:12 UTCEG score recompute
  13. 2026-06-25 13:49 UTCEPSS rescore
  14. 2026-06-25 03:45 UTCEG score recompute
  15. 2026-06-24 15:09 UTCEG score recompute
  16. 2026-06-24 14:05 UTCEPSS rescore
  17. 2026-06-24 02:43 UTCEG score recompute
  18. 2026-06-23 21:33 UTCEPSS rescore
  19. 2026-06-23 21:33 UTCEPSS rescore
  20. 2026-06-23 14:16 UTCEG score recompute
  21. 2026-06-23 01:14 UTCEG score recompute
  22. 2026-06-22 14:25 UTCEPSS rescore
  23. 2026-06-22 14:25 UTCEPSS rescore
  24. 2026-06-22 12:47 UTCEG score recompute
  25. 2026-06-22 00:19 UTCEG score recompute
  26. 2026-06-21 14:56 UTCEPSS rescore
  27. 2026-06-21 14:56 UTCEPSS rescore
  28. 2026-06-21 11:52 UTCEG score recompute
  29. 2026-06-21 01:59 UTCEPSS rescore
  30. 2026-06-21 01:59 UTCEPSS rescore
  31. 2026-06-20 23:26 UTCEG score recompute
  32. 2026-06-20 10:58 UTCEG score recompute
  33. 2026-06-19 22:29 UTCEG score recompute
  34. 2026-06-19 19:26 UTCEPSS rescore
  35. 2026-06-19 19:26 UTCEPSS rescore
  36. 2026-06-19 10:02 UTCEG score recompute
  37. 2026-06-18 21:35 UTCEG score recompute
  38. 2026-06-18 17:52 UTCEPSS rescore
  39. 2026-06-18 17:52 UTCEPSS rescore
  40. 2026-06-18 09:09 UTCEG score recompute
  41. 2026-06-17 20:41 UTCEG score recompute
  42. 2026-06-17 17:53 UTCEPSS rescore
  43. 2026-06-17 08:15 UTCEG score recompute
  44. 2026-06-17 08:15 UTCGHSA enrichment
  45. 2026-06-16 19:50 UTCEG score recompute
  46. 2026-06-16 19:48 UTCNVD updatefirst tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53840?
CVE-2026-53840 is a high vulnerability published on June 16, 2026. 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…
When was CVE-2026-53840 disclosed?
CVE-2026-53840 was first published in the National Vulnerability Database on June 16, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53840 actively exploited?
CVE-2026-53840 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 12.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53840?
CVE-2026-53840 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2026-53840?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53840, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-53840

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