Figma Mcp Bridge (atezer) MCP Server

In the server's implementation (`f-mcp-plugin/code.js:641`): Evaluating a runtime value as code (rather than a fixed literal) executes whatever reaches it — a direct RCE primitive, and almost never necessary in legitimate code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: E codePromise = eval(wrappedCode); } catch (syntaxError) { // Log the actual syntax error message

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server f-mcp-plugin/code.js

The implementation both builds shell commands out of runtime values (`dist/core/plugin-bridge-server.js`) and evaluates runtime values as code (`f-mcp-plugin/code.js`). Each is a separate arbitrary-execution primitive; a server exposing both gives anything that reaches either one a direct path to running attacker-chosen code. These two sinks are in different files — confirm whether they are actually connected, or are unrelated code paths (e.g. a vendored bundle plus a CLI wrapper).

Fix: Remove the dynamic eval, and pass command arguments as an argv array instead of building a shell string. If both are genuinely required, constrain and validate every value that can reach them.

Location: server implementation

In the server's implementation (`f-mcp-plugin/code.js:641`): Evaluating strings as code is the most direct RCE primitive; if any tool input reaches it, the server executes attacker-chosen code. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: E codePromise = eval(wrappedCode); } catch (syntaxError) { // Log the actual syntax error message

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server f-mcp-plugin/code.js

In the server's implementation (`dist/core/plugin-bridge-server.js:20`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: port { execSync } from "child_process"; import { logger } from "./logger.js"; import { auditTool, auditPlugin } from "./

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server dist/core/plugin-bridge-server.js

In the server's implementation (`dist/local-plugin-only.js:2135`): A hardcoded outbound call to a fixed external host inside server code is a classic exfiltration/telemetry channel — especially paired with reads of local data. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: const res = await fetch("https://api.figma.com/v1/me", { headers: { "X-Figma-Token": token },

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server dist/local-plugin-only.js

In the server's implementation (`dist/core/plugin-bridge-server.js:72`): A shell/process command assembled from concatenated or interpolated values is command injection when any part is attacker-influenced — the OWASP canonical RCE flow. Verify what reaches the interpolated value. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: const line = execSync(`ps -p ${pid} -o ppid=,comm=`, { timeout: 1000 }).toString().trim(); co

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server dist/core/plugin-bridge-server.js

In the server's implementation (`dist/core/bootstrap-injector.js:90`): Loading a module chosen at runtime (from a variable) can pull in and run attacker-influenced code paths. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.

Evidence: secenek sun (a) library import (b) figma_create_mini_ds (c) template (d) linter-off — secim yapmadan createFrame YASAK";

Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.

Location: server dist/core/bootstrap-injector.js