registry / @hetalhouse/fiddle / 0.2.3

@hetalhouse/fiddle@0.2.3

Scaffold and run throwaway framework sandboxes ('fiddles') — delegates to official scaffolders (Vite, Angular CLI…) where they exist, ships curated templates where they don't.

AI Security Review

scanned 4d ago · by lpm-firewall-ai

No confirmed malicious attack surface. Risky primitives are part of an explicit scaffold/build/publish CLI for managing local fiddle projects, not install-time or import-time behavior.

Static reason

One or more suspicious static signals were detected.

Trigger

Explicit user invocation of fiddle subcommands such as setup, create, start, preview, or publish.

Impact

Creates, builds, previews, or publishes user-selected fiddle projects; no credential harvesting, exfiltration, persistence, or remote code loader found.

Mechanism

CLI scaffolding, local file generation, optional npm/git/playwright helper commands.

Rationale

Static inspection shows a normal scaffold/portfolio CLI with user-invoked shell and file writes aligned to its stated purpose. No lifecycle execution, exfiltration, stealth persistence, destructive behavior beyond explicit delete/publish operations, or unconsented broad AI-agent control mutation was found.

Evidence

package.jsondist/cli.jsdist/core.jsdist/config.jsdist/registry.jsdist/portfolio.jsdist/screenshot.jsdist/defaults.jstemplates~/.fiddle/config.json$FIDDLE_HOME or ~/fiddles/<framework>/<fiddle>/CLAUDE.md$FIDDLE_HOME or ~/fiddles/<framework>/<fiddle>/README.md$FIDDLE_HOME or ~/fiddles/<framework>/<fiddle>/.fiddle.json<publishRepo>/index.html<publishRepo>/manifest.json<publishRepo>/f/**<publishRepo>/thumbs/**

Decision evidence

public snapshot

AI called this Clean at 90.0% confidence as Benign with low false-positive risk.

Evidence for block

dist/core.js uses shell:true spawn wrappers for CLI commands.
dist/cli.js writes CLAUDE.md, README.md, .fiddle.json into user-created fiddle dirs.
dist/cli.js publish path can run npm install/build and git add/commit/push on configured repo.

Evidence against

package.json has no install/preinstall/postinstall hooks; only prepublishOnly build.
dist/cli.js actions are Commander subcommands, activated by explicit fiddle CLI use.
dist/config.js only reads FIDDLE_HOME and writes ~/.fiddle/config.json for package config.
dist/registry.js delegates scaffolding to npm create vite or bundled templates; no remote payload loader found.
dist/portfolio.js escapes README-derived manifest text and uses textContent for rendered metadata.
templates contain simple Vite/Node demo starters with normal dependencies.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStringsUrlStrings

ManifestNo manifest risk signals triggered.

scanned 16 file(s), 98.1 KB of source, external domains: github.com

Source & flagged code

3 flagged

dist/core.jsView file

Lines 1-42javascript

1import { spawn } from 'node:child_process';

2import fs from 'node:fs';

High

Child Process

Package source references child process execution.

dist/core.jsView on unpkg · L1

3import path from 'node:path';

4import { fileURLToPath } from 'node:url';

5import { REGISTRY } from './registry.js';

6import { loadConfig, resolveHome } from './config.js';

7import { PLAYWRIGHT_CONFIG, SMOKE_SPEC, claudeMd, readmeMd } from './defaults.js';

8/** fiddle-0011-PlanetTween → "Planet Tween" — display title for a fresh README. */

9export function humanizeName(dirName) {

10 return dirName

11 .replace(/^fiddle-\d+-/, '')

12 .replace(/[-_]+/g, ' ')

13 .replace(/([A-Z]+)([A-Z][a-z])/g, '$1 $2')

14 .replace(/([a-z\d])([A-Z])/g, '$1 $2')

15 .replace(/\s+/g, ' ')

16 .trim();

17}

18const HERE = path.dirname(fileURLToPath(import.meta.url));

19export const TEMPLATES_DIR = path.resolve(HERE, '../templates');

20/** Run a shell command string in `cwd`, inheriting stdio. Rejects on non-zero exit. */

21export function runShell(cmd, cwd) {

22 return new Promise((resolve, reject) => {

23 const child = spawn(cmd, { cwd, stdio: 'inherit', shell: true });

24 child.on('error', reject);

High

Shell

Package source references shell execution.

dist/core.jsView on unpkg · L22

25 child.on('close', (code) => code === 0 ? resolve() : reject(new Error(`\`${cmd}\` exited with code ${code}`)));

26 });

27}

28/**

29 * Best-effort shell: resolves true on a clean exit, false on error / non-zero /

30 * timeout. Never throws, never inherits stdio. For publishing an archive where

31 * a decade-old `npm install` may fail or hang — we skip it and move on.

32 */

33export function tryShell(cmd, cwd, timeoutMs = 120_000) {

34 return new Promise((resolve) => {

35 const child = spawn(cmd, { cwd, stdio: 'ignore', shell: true, detached: true });

36 const timer = setTimeout(() => {

37 try {

38 process.kill(-child.pid, 'SIGKILL'); // kill the whole process group (npm children)

39 }

40 catch {

41 child.kill('SIGKILL');

42 }

dist/cli.jsView file

Lines 1-23javascript

1#!/usr/bin/env node

2import { Command } from 'commander';

3import { createInterface } from 'node:readline/promises';

4import { execSync } from 'node:child_process';

5import fs from 'node:fs';

6import os from 'node:os'

Source & flagged code

3 flagged · loading source

dist/core.jsView file

1import { spawn } from 'node:child_process'; L2: import fs from 'node:fs';

High

Child Process

Package source references child process execution.

dist/core.jsView on unpkg · L1

22return new Promise((resolve, reject) => { L23: const child = spawn(cmd, { cwd, stdio: 'inherit', shell: true }); L24: child.on('error', reject);

High

Shell

Package source references shell execution.

dist/core.jsView on unpkg · L22

dist/cli.jsView file

3Cross-file remote execution chain: dist/cli.js spawns dist/portfolio.js; helper contains network access plus dynamic code execution. L3: import { createInterface } from 'node:readline/promises'; L4: import { execSync } from 'node:child_process'; L5: import fs from 'node:fs'; ... L23: async function prompt(q) { L24: const rl = createInterface({ input: process.stdin, output: process.stdout }); L25: const a = (await rl.question(c.amber(` ${q} `))).trim(); ... L31: try { L32: execSync(process.platform === 'win32' ? `where ${bin}` : `command -v ${bin}`, { stdio: 'ignore' }); L33: return true; ... L125: try { L126: await runShell('npx --yes playwright install chromium', process.cwd()); L127: console.log(` ${c.green('✓')} Chromium installed`);

High

Cross File Remote Execution Context

Source spawns a local helper that also contains network and dynamic execution context; review data flow before blocking.

dist/cli.jsView on unpkg · L3

Findings

3 High2 Medium5 Low

HighChild Processdist/core.js

HighShelldist/core.js

HighCross File Remote Execution Contextdist/cli.js

MediumNetwork

MediumEnvironment Vars

LowNon Install Lifecycle Scripts

LowScripts Present

LowFilesystem

LowHigh Entropy Strings

LowUrl Strings

Source & flagged code

3 flagged

dist/core.jsView file

Lines 1-42javascript

1import { spawn } from 'node:child_process';

2import fs from 'node:fs';

High

Child Process

Package source references child process execution.

dist/core.jsView on unpkg · L1

3import path from 'node:path';

4import { fileURLToPath } from 'node:url';

5import { REGISTRY } from './registry.js';

6import { loadConfig, resolveHome } from './config.js';

7import { PLAYWRIGHT_CONFIG, SMOKE_SPEC, claudeMd, readmeMd } from './defaults.js';

8/** fiddle-0011-PlanetTween → "Planet Tween" — display title for a fresh README. */

9export function humanizeName(dirName) {

10 return dirName

11 .replace(/^fiddle-\d+-/, '')

12 .replace(/[-_]+/g, ' ')

13 .replace(/([A-Z]+)([A-Z][a-z])/g, '$1 $2')

14 .replace(/([a-z\d])([A-Z])/g, '$1 $2')

15 .replace(/\s+/g, ' ')

16 .trim();

17}

18const HERE = path.dirname(fileURLToPath(import.meta.url));

19export const TEMPLATES_DIR = path.resolve(HERE, '../templates');

20/** Run a shell command string in `cwd`, inheriting stdio. Rejects on non-zero exit. */

21export function runShell(cmd, cwd) {

22 return new Promise((resolve, reject) => {

23 const child = spawn(cmd, { cwd, stdio: 'inherit', shell: true });

24 child.on('error', reject);

High

Shell

Package source references shell execution.

dist/core.jsView on unpkg · L22

25 child.on('close', (code) => code === 0 ? resolve() : reject(new Error(`\`${cmd}\` exited with code ${code}`)));

26 });

27}

28/**

29 * Best-effort shell: resolves true on a clean exit, false on error / non-zero /

30 * timeout. Never throws, never inherits stdio. For publishing an archive where

31 * a decade-old `npm install` may fail or hang — we skip it and move on.

32 */

33export function tryShell(cmd, cwd, timeoutMs = 120_000) {

34 return new Promise((resolve) => {

35 const child = spawn(cmd, { cwd, stdio: 'ignore', shell: true, detached: true });

36 const timer = setTimeout(() => {

37 try {

38 process.kill(-child.pid, 'SIGKILL'); // kill the whole process group (npm children)

39 }

40 catch {

41 child.kill('SIGKILL');

42 }

dist/cli.jsView file

Lines 1-23javascript

1#!/usr/bin/env node

2import { Command } from 'commander';

3import { createInterface } from 'node:readline/promises';

4import { execSync } from 'node:child_process';

5import fs from 'node:fs';

6import os from 'node:os'