High, CVSS 7.5npmPublished
faf-mcp has an arbitrary local file read/write via unconfined path argument in FAF tools
GHSA-j4r7-8ph4-43g3
- Affected
- npm faf-mcp <= 2.1.2
- Fixed in
- 2.1.3· Vendor fix available
- Issue
- faf-mcp MCP tools accept a caller-controlled path argument and resolve it (~ expansion + path.resolve()) straight into a filesystem read/write without confining it to a trusted project directory. An absolute path or ../ traversal is resolved and used as-is, so the server process can be made to read — and, via the file tools, write — files outside the intended .faf project context. The only remaining limit is OS file permissions. Affected tools The shared getProjectPath() chokepoint (feeding the .faf tools) and the general-purpose fafread / fafwrite file tools resolved a caller path straight into a read/write with no confinement (denylist-only); an absolute path still reached home-directory secrets, and fafwrite could write outside the project. Impact An MCP client — or an LLM prompt-injected via attacker-controlled content (a web page, README, ticket, or .faf) into issuing a tool call — can read any file the server process can read: SSH keys (~/.ssh/idrsa), cloud credentials…
Recommended action: Upgrade to 2.1.3 or later, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.