CVE-2026-66005

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 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/janhq/jan/commit/3e1c1e724f696620d89bb4a9cc18a380e0753757
https://github.com/janhq/jan/issues/8453
https://github.com/janhq/jan/pull/8506
https://www.vulncheck.com/advisories/jan-local-api-server-cors-origin-reflection-via-binding

Configurations

No configuration.

History

24 Jul 2026, 15:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-24 15:19

Updated : 2026-07-30 20:16

NVD link : CVE-2026-66005

Mitre link : CVE-2026-66005

CVE.ORG link : CVE-2026-66005

JSON object : View

Products Affected

No product.

CWE

CWE-183

Permissive List of Allowed Inputs

CWE-942

Permissive Cross-domain Policy with Untrusted Domains

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