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TI-2026-47003 Aliases CVE-2026-66005GHSA-4r96-7xrx-4gcr

Jan Local API Server CORS Origin Reflection via 0.0.0.0 Binding

Priority MEDIUM 57CWE-183Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · Low · Low
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00331 26th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
janhqjanup to 0.8.4—Patch availableCNA
  • jan Vendorjanhq Affected up to 0.8.4 Fixed in — Patch available CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66005
  2. 2026-10-03 Alias added: GHSA-4r96-7xrx-4gcr

References

Exploit 1

Patch 2

  • TI-2026-85208 Workspace guard bypass in Jan lets attackers write files outside workspace CVSS 4.0MEDIUM 5.7

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences