CVE-2026-66005

MEDIUMPre-NVD 6.36.3—
EchelonGraph scoreHIGH confidence

Score 6.3 from GitHub Security Advisory published 2026-07-24. the CNA's CVSS baseline 6.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:vulncheck, epss, ghsa
Trending — 4 sources updated this weekElevated
6.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.3Exploit: Elevated riskExposed: 0

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

Jan through 0.8.4, fixed in commit 3e1c1e7, contains a CORS misconfiguration vulnerability in its local API server that allows network-adjacent attackers to bypass trusted host restrictions by exploiting the server's replacement of user-configured trusted hosts with a wildcard that reflects arbitrary origins with credentials. Attackers on the local network or using DNS rebinding can reach the unauthenticated OpenAI-compatible API to perform inference, enumerate models, invoke MCP tools, and read cross-origin responses.

CVSS v3
6.3
EG Score
6.3(high)
EG Risk
44(Track)
EG Risk 44/100SSVC: Track

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
Severity63% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
9%
KEV
Not listed

Published

July 24, 2026

Last Modified

July 25, 2026

Advisory Details (4)

Auto-updated Jul 24, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit, github_pr.
generic

Jan Local API Server CORS Origin Reflection via 0.0.0.0 Binding | Advisories | VulnCheck

https://www.vulncheck.com/advisories/jan-local-api-server-cors-origin-reflection-via-binding
github_pr

fix: enforce Trusted Hosts allowlist when binding 0.0.0.0 (GHSA-x6p8-7cp8-c3p6)

Fix merged in janhq/jan PR #8506 on 2026-07-24 — awaiting tagged release

https://github.com/janhq/jan/pull/8506
generic

Issue · GitHub

https://github.com/janhq/jan/issues/8453
github_commit

commit 3e1c1e724f69 (janhq/jan)

Fix landed in janhq/jan commit 3e1c1e724f69 — awaiting tagged release

https://github.com/janhq/jan/commit/3e1c1e724f696620d89bb4a9cc18a380e0753757

Vendor Advisories for CVE-2026-66005(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 10× 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. 2026-07-27 01:58 UTCEG score recompute
  2. 2026-07-27 01:58 UTCGHSA enrichment
  3. 2026-07-26 14:54 UTCEPSS rescore
  4. 2026-07-26 14:54 UTCEPSS rescore
  5. 2026-07-26 03:00 UTCEG score recompute
  6. 2026-07-26 03:00 UTCGHSA enrichment
  7. 2026-07-25 14:18 UTCEPSS rescore
  8. 2026-07-25 14:18 UTCEPSS rescore
  9. 2026-07-24 15:13 UTCEG score recompute
  10. 2026-07-24 15:13 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-66005?
CVE-2026-66005 is a medium vulnerability published on July 24, 2026. Jan through 0.8.4, fixed in commit 3e1c1e7, contains a CORS misconfiguration vulnerability in its local API server that allows network-adjacent attackers to bypass trusted host restrictions by exploiting the server's replacement of user-configured trusted hosts with a wildcard that reflects…
When was CVE-2026-66005 disclosed?
CVE-2026-66005 was first published in the National Vulnerability Database on July 24, 2026, with the most recent update on July 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66005 actively exploited?
CVE-2026-66005 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 91.4% of all scored CVEs.
What is the CVSS score of CVE-2026-66005?
CVE-2026-66005 has a CVSS v4.0 base score of 6.3 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-66005?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66005, 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

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