CVE-2026-66005
Jan Local API Server CORS Origin Reflection via 0.0.0.0 Binding
CVSS Score
6.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-183 CWE-942 |
| Vendor | janhq |
| Product | jan |
| Published | Jul 24, 2026 |
| Last Updated | Jul 24, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low
Affected Versions
janhq / jan
0 ≤ 0.8.4
References
github.com: https://github.com/janhq/jan/issues/8453 github.com: https://github.com/janhq/jan/pull/8506 github.com: https://github.com/janhq/jan/commit/3e1c1e724f696620d89bb4a9cc18a380e0753757 vulncheck.com: https://www.vulncheck.com/advisories/jan-local-api-server-cors-origin-reflection-via-binding
Credits
George Chen