CVE-2026-100538

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory (severity: HIGH) published 2026-09-26. A secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 6.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

OpenClaw (npm package 'openclaw') before 2026.8.1 does not apply the originating sender's global or per-agent toolsBySender policy when handling outbound attachments. A sender that has been explicitly denied filesystem read tools can still cause a known local file to be read and returned via a final-response media directive or a message attachment, disclosing local file contents to an admitted requester whose agent turn did not include the read tool. Exploitation requires knowledge or derivation of a useful host path and a delivery flow that accepts local attachments. The issue is fixed in version 2026.8.1.

CVSS v3
6.5
EG Score
6.5MEDIUMhigh confidence
EG Risk
29
EG Risk 29/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.3%
EPSS %ILE
15th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 26, 2026

Last Modified

September 28, 2026

Advisory Details (2)

Auto-updated Sep 26, 2026
Patch available. Sources: github.
generic Patch Available

OpenClaw before 2026.8.1 Local File Read via Outbound Attachments | Advisories | VulnCheck

https://www.vulncheck.com/advisories/openclaw-before-2026.8.1-local-file-read-via-outbound-attachments
github Patch Available

Outbound attachments could ignore requester read denials · Advisory · openclaw/openclaw · GitHub

https://github.com/openclaw/openclaw/security/advisories/GHSA-w5x7-c87m-3jpc

Vendor Advisories for CVE-2026-100538(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 29× 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. 2026-10-03 16:04 UTCEG score recompute
  2. 2026-10-03 16:04 UTCGHSA enrichment
  3. 2026-10-03 14:25 UTCEPSS rescore
  4. 2026-10-02 16:38 UTCEG score recompute
  5. 2026-10-02 16:38 UTCGHSA enrichment
  6. 2026-10-01 19:49 UTCEPSS rescore
  7. 2026-10-01 17:07 UTCGHSA enrichment
  8. 2026-09-30 17:41 UTCEG score recompute
  9. 2026-09-30 17:41 UTCGHSA enrichment
  10. 2026-09-30 15:02 UTCEPSS rescore
  11. 2026-09-29 18:14 UTCEG score recompute
  12. 2026-09-29 18:14 UTCGHSA enrichment
  13. 2026-09-29 15:20 UTCEPSS rescore
  14. 2026-09-28 18:22 UTCEG score recompute
  15. 2026-09-28 18:22 UTCGHSA enrichment
  16. 2026-09-28 17:57 UTCEG score recompute
  17. 2026-09-28 17:56 UTCGHSA enrichment
  18. 2026-09-28 15:32 UTCEG score recompute
  19. 2026-09-28 15:32 UTCGHSA enrichment
  20. 2026-09-28 13:50 UTCEPSS rescore
  21. 2026-09-28 02:25 UTCEG score recompute
  22. 2026-09-28 02:25 UTCGHSA enrichment
  23. 2026-09-27 02:59 UTCEG score recompute
  24. 2026-09-27 02:59 UTCGHSA enrichment
  25. 2026-09-26 15:58 UTCEPSS rescore
Show 4 more
  1. 2026-09-26 03:32 UTCEG score recompute
  2. 2026-09-26 03:31 UTCGHSA enrichment
  3. 2026-09-26 02:33 UTCEG score recompute
  4. 2026-09-26 02:29 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-100538?
CVE-2026-100538 is a medium vulnerability published on September 26, 2026. OpenClaw (npm package 'openclaw') before 2026.8.1 does not apply the originating sender's global or per-agent toolsBySender policy when handling outbound attachments. A sender that has been explicitly denied filesystem read tools can still cause a known local file to be read and returned via a…
When was CVE-2026-100538 disclosed?
CVE-2026-100538 was first published on September 26, 2026, with the most recent update on September 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-100538 actively exploited?
CVE-2026-100538 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (15th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100538?
CVE-2026-100538 has a CVSS base score of 6.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100538?
A fix for CVE-2026-100538 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-100538 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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