registry / AI-agent capability abuse / pennyrouter / 0.3.43

pennyrouter@0.3.43

Install and manage PennyRouter local coding-agent integrations.

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The package provides user-invoked setup that writes agent configuration and registers an MCP server, so the capability merits a warning. Inspected source does not establish malicious behavior or automatic npm-install execution.

Static reason

One or more suspicious static signals were detected.; previous stored version diff introduced dangerous source

Trigger

A user runs the explicit install command and selects a supported harness.

Impact

The harness gains PennyRouter routing and MCP integration; inspected source does not establish an active attack.

Mechanism

Installation writes Claude Code skill and launch settings and can register the Threads MCP server in supported harness configuration.

AI rationale

Evidence

package.jsonsrc/cli.jssrc/launch.jssrc/mcp-register.js

Decision evidence

public snapshot

AI called this Suspicious at 88.0% confidence as Dangerous Capability with medium false-positive risk.

Evidence for warning

package.json exposes a command-line entry point and defines only start and check scripts, with no npm install lifecycle hook.
The explicit install command configures selected harnesses; Claude Code setup writes a user skill and launch settings.
The installer registers the Threads MCP server unless the user passes --no-mcp; registration updates supported harness configuration.
The remaining flagged locations inspected concern test fixtures, local session or transcript reads, and the standalone demo; they do not establish an attack.
The CodeGPT integration shows manual setup instructions and avoids modifying IDE settings.

Evidence against

No source inspected establishes automatic execution during npm installation, credential theft, or an unrelated remote payload.

Behavioral surface

Source

ChildProcessCryptoEnvironmentVarsFilesystemNetworkShellWebSocket

Supply chain

Source & flagged code

10 flagged

standalone/web-demo/server.mjsView file

Lines 1-23javascript

1import { createServer } from 'node:http';

2import { randomUUID } from 'node:crypto';

3import { mkdtemp, readFile, rm, stat, writeFile } from 'node:fs/promises';

4import { spawn, execFile } from 'node:child_process';

5import { join, dirname, resolve } from 'node:path';

High

Child Process

Package source references child process execution.

standalone/web-demo/server.mjsView on unpkg · L3

6import { homedir, tmpdir } from 'node:os';

7import { fileURLToPath } from 'node:url';

8import { promisify } from 'node:util';

9import { WebSocketServer } from 'ws';

10import pty from 'node-pty';

11import { ClaudeMeter, CodexMeter, saveReport } from './claude-meter.mjs';

12import { listArtifacts, readArtifact } from './artifacts.mjs';

14const here = dirname(fileURLToPath(import.meta.url));

15const compareDir = dirname(here);

16const execFileAsync = promisify(execFile);

17const args = process.argv.slice(2);

18const claude = args.includes('--claude');

19const harnessArg = args.find((arg) => /^--harness=(claude|codex)$/.test(arg));

20const startupHarness = harnessArg?.slice('--harness='.length) || 'claude';

21const nodeMeter = args.includes('--compare-node') ||

22 (args.includes('--compare') && process.platform === 'win32');

23const compare = args.includes('--compare') || nodeMeter;

Lines 284-321javascript

284 session.onData((data) => send({ type: 'output', side: message.side, data }));

285 session.onExit(({ exitCode }) => {

286 sessions.delete(message.side);

287 send({ type: 'exit', side: message.side, code: exitCode });

src/launch.jsView file

Lines 348-388javascript

348 let replace = false;

349 try {

350 replace = (await lstat(link)).isSymbolicLink();

351 } catch (error) {

352

src/launch.test.jsView file

Lines 1-21javascript

1import assert from "node:assert/strict";

2import { spawnSync } from "node:child_process";

3import fs from "node:fs";

Medium

Install Persistence

Source writes installer persistence such as shell profile or service configuration.

src/launch.test.jsView on unpkg · L1

4import

src/harnesses/codegpt.jsView file

Lines 1-21javascript

1import { spawnSync } from "node:child_process";

High

Sandbox Evasion Gated Capability

Source gates dangerous network, credential, or execution behavior behind CI, host, platform, time, or geo fingerprint checks.

src/harnesses/codegpt.jsView on unpkg · L1

3export const codeGptHarness = {

4 id: "codegpt",

src/statusline.jsView file

•Runtime or CLI code links a write operation to an explicit external AI-agent control path: tatusline (all lines) |] penny segment (penny / penny (sub) // / penny (byok) / penny off). the wrapped statusline's first line gets the penny suffix; // any further lines (e.g. a context bar) pass through verbatim. // never blocks on the network: reads a per-session cache and refreshes it detached. import { readfilesync, mkdirsync, writefilesync, statsync } from "node:fs"; import { spawn, spawnsync } from "node:child_process"; import { join, basename } from "node:path"; import os from "node:os"; const statedir = join( process.env.xdg_state_home || join(os.homedir(), ".local", "state"), "pennyrouter", ); const cachedir = join(statedir, "statusline-cache"); const titlesessionfile = process.env.pe

High

External Ai Agent Control Surface Mutation

Runtime or CLI source writes behavior-bearing configuration into a user or project AI-agent control surface.

src/statusline.jsView on unpkg

standalone/claude-proxy.shView file

•path = standalone/claude-proxy.sh kind = build_helper sizeBytes = 8224 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

standalone/claude-proxy.shView on unpkg

src/mcp-register.js#virtual:normalized:round1View file

•stage = ast_semantic_analysis; reason = ast_parse_error; limitedFiles = 2

High

Semantic Analysis Limited

A bounded semantic-analysis stage reached its safety limit; remaining detectors completed, but this package requires AI review.

src/mcp-register.js#virtual:normalized:round1View on unpkg

src/cli.jsView file

•matchType = previous_version_dangerous_delta matchedPackage = pennyrouter@0.3.17 matchedIdentity = npm:cGVubnlyb3V0ZXI:0.3.17 similarity = 0.710 summary = stored previous version shares package body but lacks this dangerous source file

High

Previous Version Dangerous Delta

This package version adds a dangerous source file absent from the previous stored version; route for source-aware review.

src/cli.jsView on unpkg

Source & flagged code

10 flagged · loading source

standalone/web-demo/server.mjsView file

3import { mkdtemp, readFile, rm, stat, writeFile } from 'node:fs/promises'; L4: import { spawn, execFile } from 'node:child_process'; L5: import { join, dirname, resolve } from 'node:path';

High

Child Process

Package source references child process execution.

standalone/web-demo/server.mjsView on unpkg · L3

304server.listen(port, '127.0.0.1', () => { L305: const url = `http://127.0.0.1:${port}`; L306: console.log(`Penny Compare live terminal demo: ${url}`); ... L310: if (process.platform === 'win32') { L311: execFile(process.env.ComSpec || 'cmd.exe', ['/d', '/s', '/c', `start "" "${url}"`], L312: { windowsHide: true }, (error) => {

High

Same File Env Network Execution

A single source file combines environment access, network access, and code or shell execution; review context before blocking.

standalone/web-demo/server.mjsView on unpkg · L304

src/launch.jsView file

368const body = process.platform === "win32" L369: // `node` and the native harnesses are normally npm .cmd shims on Windows. cmd.exe L370: // resolves those through PATHEXT, while Node's direct spawn does not.

Findings

8 High5 Medium4 Low

HighChild Processstandalone/web-demo/server.mjs

HighShellsrc/launch.js

HighSame File Env Network Executionstandalone/web-demo/server.mjs

HighSandbox Evasion Gated Capabilitysrc/harnesses/codegpt.js

HighExternal Ai Agent Control Surface Mutationsrc/statusline.js

HighTrigger Reachable External Ai Agent Control Surface Mutationsrc/launch.js

HighSemantic Analysis Limitedsrc/mcp-register.js#virtual:normalized:round1

HighPrevious Version Dangerous Deltasrc/cli.js

MediumNetwork

MediumEnvironment Vars

MediumInstall Persistencesrc/launch.test.js

MediumShips Build Helperstandalone/claude-proxy.sh

Affected versions and remediation

This report applies to pennyrouter@0.3.43.

See all versions of pennyrouter for other recorded verdicts.

Review the evidence and your use of pennyrouter@0.3.43 before allowing it. Restrict the permissions described in this report.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.

Evidence last updated: 2026-10-11 19:05:34.072Z (UTC).

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