Jan Local API Server CORS Origin Reflection via 0.0.0.0 Binding
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 5.3epss 0.2%
exploitation probability
0.2%top 91% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
Affected products
janhq · janpublic PoCs found — 1
cve_referencegithub.com/janhq/jan/issues/8453unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.