If you discover a security vulnerability in mcp-browser, please report it privately.
Do not open a public GitHub issue. Instead, send a detailed report via the Security tab at:
https://github.com/schiz0x00/mcp-browser/security/advisories/new
You should receive a response within 48 hours. If you do not, please follow up.
This server drives a real browser and fetches arbitrary URLs on behalf of its clients. In-scope: SSRF and the allowlist bypasses around it, API-key authentication bypass, escape from per-session browser isolation, leakage of captured request/response traffic across sessions, and resource exhaustion.
Out of scope: anything that requires the operator to have opted into it.
ALLOW_EVALUATE, ALLOW_COOKIES and ALLOW_PRIVATE_IPS all default to
false and are documented as dangerous in .env.example; turning one on and
reaching the capability it grants is the feature working, not a vulnerability.
Only the latest tagged release receives security patches.