Skills/npm/fsb-mcp-server

fsb-mcp-server@0.11.5

VERIFIED· startup only

Publisher claims: "FSB Browser Automation MCP Server" Observed in sandbox: no network, touches nothing outside the project, writes no memory.

Registry npm (MCP server)Publisher fullselfbrowsing · publishing for 234 daysInstalls 342Last detonated 18 h ago
$claude mcp add fsb-mcp-server -- npx -y fsb-mcp-server
WatchReport an issue

Coverage

Startup only; authenticated tool behavior not tested.
Tested
server startup over stdio (initialize sent) · every file read, file written and host contacted by what ran
Not tested
the tool list (the server exited before answering) · what the tools do when called with real credentials

What this means for the label: Verified here covers what ran. The server's tools were not exercised with a real credential, so nothing about their behavior is asserted; the credential summary below says what to do with that.

Before you give it your token

It will ask for
no credential variables read in the code
Where it talks to
no vendor host named in the codeAlso amazon.com, google.com — not the publisher's domain; check what for before connecting.
What the honeypot saw
no credential files read · no network
What we could not test
the tool list (the server exited before answering) · what the tools do when called with real credentials

Connect it under the guard. Startup only; authenticated tool behavior not tested. The code names no credential variable; the guard pins the network to what the honeypot saw and logs every call.

$vet-skills run --net declared -- npx -y fsb-mcp-server

Never paste a credential into a chat, a ticket or a report, including ours. How the guard holds it.

Is [email protected] safe to install?

KillerSkills ran it in the KillerSkills honeypot sandbox (2 scenarios; startup only; authenticated tool behavior not tested) on 2026-11-13 and scored it 83/100 (Verified). In what ran, nothing we could detect went wrong: no undeclared network egress, no credential reads, no persistent instruction writes. What it does with a real credential was not observed; the static findings and the publisher carry the rest of the score. Summary: no network, touches nothing outside the project, writes no memory.

Behavior trace

Honeypot run · 28 s · 2 scenarios · 0 deviations
t+CategoryObserved action
0.0sprocessno install scripts in bundle
7.4sprocessdependency install exit 0
27sclaimedstartup only: exited (0) before answering · code: 'ERR_MODULE_NOT_FOUND', url: 'file:///tmp/ks-detonate-qNKMsG/task/home/work/acme-api/.claude/skills/fsb-mcp-server/build/agent-providers/serve-delegation.js' } Node.js v22.23.5
27sprocessscript backend runs setup only
27sprocessno install scripts to re-run

Static findings

HIGH
Access to sensitive file pathsai/tool-definitions.cjs:1427 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system files…ut, fall back to drop_file. Security: a sensitive-path denylist blocks secrets (~/.ssh, ~/.aws, .env, private keys, the FSB vault) and every upload is audit-logged. R…Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05
HIGH
Access to sensitive file pathsbuild/install.js:299 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system filesreturn 'Restart Amazon Q CLI or IDE after editing ~/.aws/amazonq/mcp.json.';Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05
HIGH
Access to sensitive file pathsbuild/install.js:554 · Access to sensitive file paths — SSH keys, AWS credentials, env files, or system files'Config: ~/.aws/amazonq/mcp.json',Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST05
MEDIUM
Process kill commandbuild/agent-providers/grok.js:11 · Process kill command — agent can terminate processesthrow new TypeError('Grok Build adapter requires a tree-kill dependency');Fix: Build commands from fixed arguments; do not interpolate untrusted strings into a shell.
AST05
MEDIUM
npx invocation of non-well-known packagebuild/diagnostics.js:634 · npx invocation of non-well-known package — may execute untrusted codenextAction: 'Run `npx -y fsb-mcp-server@latest pair --reset`, then fully quit and reopen the browser.',Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/install.js:180 · npx invocation of non-well-known package — may execute untrusted codeconsole.error('Run npx -y fsb-mcp-server@latest doctor for repair details.');Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/install.js:11 · npx invocation of non-well-known package — may execute untrusted codeconst WINDOWS_STDIO_COMMAND = 'cmd /c npx -y fsb-mcp-server@latest';Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
MCP server using network transport (SSE/HTTP)build/index.js:94 · MCP server using network transport (SSE/HTTP) — data sent over networkfsb-mcp-server serve Start a local Streamable HTTP MCP serverFix: Namespace tool names and keep tool descriptions literal; no instructions to the agent inside them.
AST04
MEDIUM
npx invocation of non-well-known packagebuild/platforms.js:307 · npx invocation of non-well-known package — may execute untrusted code* On Windows, wraps npx as `cmd /c npx` per INST-07.Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/bridge.js:531 · npx invocation of non-well-known package — may execute untrusted code+ 'Cure: npx -y fsb-mcp-server@latest pair --reset');Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/index.js:281 · npx invocation of non-well-known package — may execute untrusted codelines.push('- Stdio: npx -y fsb-mcp-server@latest');Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/platforms.d.ts:65 · npx invocation of non-well-known package — may execute untrusted code* On Windows, wraps npx as `cmd /c npx` per INST-07.Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/install.js:338 · npx invocation of non-well-known package — may execute untrusted codeconsole.log(' npx -y fsb-mcp-server@latest serve');Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/install.js:10 · npx invocation of non-well-known package — may execute untrusted codeconst STDIO_COMMAND = 'npx -y fsb-mcp-server@latest';Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
npx invocation of non-well-known packagebuild/install.js:348 · npx invocation of non-well-known package — may execute untrusted codeconsole.log(' npx -y fsb-mcp-server@latest serve');Fix: Pin versions and sources; vendor anything fetched at install time.
AST06
MEDIUM
Process kill commandbuild/agent-providers/grok.js:10 · Process kill command — agent can terminate processesif (!dependencies || typeof dependencies.kill !== 'function') {Fix: Build commands from fixed arguments; do not interpolate untrusted strings into a shell.
AST05

Cost to the agent

Instructions loaded
≈46 tok
1 file · 81 in bundle
Tool list per prompt
≈0 tok
0 tools · 0 per tool
Handshake
no reply
launch to tools/list, stdio
Undocumented tools
0
description under 20 chars · avg 0

Tokens estimated at four characters each. The tool list is re-read by the agent on every turn, so it is the number to compare between servers that do the same job: ranked across the index.

Known vulnerabilities

No advisories in OSV for fsb-mcp-server@0.11.5 as of 18 h ago. This is the package itself, not its dependencies.