registry / AI-agent control-surface risk / @chem-x/create-chemx / 26.9.20-1257

@chem-x/create-chemx@26.9.20-1257

Chemical X Protocol: Private drop-in architecture starter kit and capsule generator

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The package performs unconsented agent configuration mutation from its npm postinstall hook, matching the policy for blocking install-time AI-agent control-surface changes. The inspected code registers the package's own MCP server and showed no credential exfiltration.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

Installing the package through npm invokes its postinstall hook.

Impact

Agent clients can load the package's MCP server without a separate user setup action.

Mechanism

The hook calls the MCP installer for the consumer directory without a consent prompt; the installer writes MCP configuration that launches the Chemical X command.

Policy narrative

On npm installation, postinstall passes the consumer directory to the MCP installer. The installer writes Cursor and VS Code MCP configuration and conditionally registers the server in existing Antigravity configuration. This is automatic agent control-surface setup; the inspected install path showed no consent gate.

AI rationale

Evidence

package.jsoncli/postinstall.jscli/mcp/installer.js.cursor/mcp.json.vscode/mcp.json~/.gemini/config/mcp_config.json

Decision evidence

public snapshot

AI identified this as a dangerous AI-agent capability at 98.0% confidence with low false-positive risk.

Evidence for policy risk

package.json defines a postinstall hook that runs cli/postinstall.js.
The hook targets the consuming directory and automatically calls installAllMcpConfigs without a consent check.
The MCP installer writes project agent configuration files and registers a Chemical X MCP command.
The MCP installer also configures Antigravity when its global configuration directory already exists.
Separate installer and wizard code contains agent configuration behavior; the wizard writes selected files only when it is not in dry-run mode.

Evidence against

The MCP registration is for the package's own Chemical X server; inspected source did not show credential collection or a network endpoint in this install path.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStringsUrlStrings

ManifestNo manifest risk signals triggered.

Source & flagged code

10 flagged

package.jsonView file

Lines 27-67json

27 "README.md",

28 "LICENSE",

29 "docs",

30 "assets"

31 ],

32 "exports": {

33 ".": "./cli/index.js",

34 "./audit": "./cli/audit.js",

35 "./build": "./cli/build.js",

36 "./search": "./cli/search.js",

37 "./mcp": "./cli/mcp/index.js",

38 "./reader": "./cli/reader.js",

39 "./patcher": "./cli/patcher.js",

40 "./errors": "./cli/errors/index.js"

41 },

42 "scripts": {

43 "chemx": "node cli/index.js",

44 "test": "node --test cli/audit/*.spec.js cli/mcp/*.spec.js cli/build/*.spec.js cli/team/*.spec.js cli/errors/*.spec.js cli/*.spec.js",

45 "typecheck": "tsc --noEmit",

46 "publish:both": "node scripts/publish-both.mjs",

47 "postinstall": "node cli/postinstall.js",

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg · L47

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg · L47

48 "chemx:mcp": "chemx mcp",

49 "chemx:verify": "chemx verify",

50 "chemx:test": "chemx test",

51 "chemx:typecheck": "chemx typecheck"

52 },

53 "dependencies": {

54 "@babel/parser": "^7.29.8",

55 "@babel/traverse": "^7.29.8",

56 "@babel/types": "^7.29.8",

57 "react": "^18.3.1",

58 "react-dom": "^18.3.1"

59 },

60 "devDependencies": {

61 "@types/babel__traverse": "^7.28.0",

62 "@types/node": "^22.20.2",

63 "@types/react": "^18.3.31",

64 "@types/react-dom": "^18.3.7",

65 "chemx": "26.9.20-408",

66 "typescript": "^5.9.3"

67 }

cli/errors/errors.spec.jsView file

27patternName = github_pat severity = critical line = 27

Critical

Critical Secret

Package contains a critical-looking secret pattern.

cli/errors/errors.spec.jsView on unpkg · L27

27patternName = github_pat severity = critical line = 27

Critical

Secret Pattern

GitHub personal access token in cli/errors/errors.spec.js

cli/errors/errors.spec.jsView on unpkg · L27

cli/audit-preflight-git.jsView file

1import fs from 'node:fs'; L2: import { spawnSync } from 'node:child_process'; L3:

High

Child Process

Package source references child process execution.

cli/audit-preflight-git.jsView on unpkg · L1

cli/build/executor.jsView file

11const child = spawn(command, { L12: shell: true, L13: cwd,

High

Shell

Package source references shell execution.

cli/build/executor.jsView on unpkg · L11

cli/license.jsView file

Lines 1-23javascript

1import fs from 'node:fs';

2import path from 'node:path';

3import os from 'node:os';

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

cli/mcp/installer.jsView file

1Install-time code directly mutates a foreign AI-agent control surface: L20: export const mergeMcpServerConfig = (existingJsonString = '', serverDef = {}) => { L21: let parsed = { mcpServers: {} }; L22: ... L30: L31: const hasMcpServersObject = Boolean(parsed.mcpServers && typeof parsed.mcpServers === 'object'); L32: if (!hasMcpServersObject) { L33: parsed.mcpServers = {}; L34: } L35: L36: parsed.mcpServers[SERVER_KEY] = serverDef; L37: return JSON.stringify(parsed, null, 2) + '\n'; ... L90: const cursorDir = path.join(resolvedTarget, '.cursor'); Write operation from cli/mcp/installer.js: L20: export const mergeMcpServerConfig = (existingJsonString = '', serverDef = {}) => { L21: let parsed = { mcpServers: {} }; L22: ... L30: L31: const hasMcpServersObject = Boolean(parsed.mcpServers &

Critical

Ai Agent Control Hijack

Source creates an unconsented AI-agent control surface through install-time mutation or a default unauthenticated remote skill channel.

cli/mcp/installer.jsView on unpkg · L1

cli/pillars-wizard.jsView file

•Manifest-trigger-reachable source links an external AI-agent control path to a behavior-bearing write operation. st pick = usegum ? gumchoose(choices, 'select architectural pillars configuration') : await promptquestion('select pillars: [1=recommended, 2=strict, 3=custom, 4=minimal, 5=none] (default: 1): '); if (pick && (pick.startswith('2.') || pick === '2')) { selectedpresetkey = 'strict'; selectedpillarids = [...pillar_presets.strict.pillars]; } else if (pick && (pick.startswith('3.') || pick === '3')) { selectedpresetkey = 'custom'; for (const pillar of pillars) { const defaultchoice = pillar_presets.recommended.pillars.includes(pillar.id) ? 'y/n' : 'y/n'; const isdefaultyes = defaultchoice === 'y/n'; const answer = a

High

Trigger Reachable External Ai Agent Control Surface Mutation

Manifest-trigger-reachable source writes behavior-bearing configuration into a user or project AI-agent control surface.

cli/pillars-wizard.jsView on unpkg

scripts/pre-commit.shView file

•path = scripts/pre-commit.sh kind = build_helper sizeBytes = 5174 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

scripts/pre-commit.shView on unpkg

Source & flagged code

10 flagged · loading source

package.jsonView file

•scripts.postinstall = node cli/postinstall.js

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

•scripts.postinstall = node cli/postinstall.js

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg

cli/errors/errors.spec.jsView file

27patternName = github_pat severity = critical line = 27

Critical

Critical Secret

Package contains a critical-looking secret pattern.

cli/errors/errors.spec.jsView on unpkg · L27

Findings

3 Critical5 High5 Medium4 Low

CriticalCritical Secretcli/errors/errors.spec.js

CriticalAi Agent Control Hijackcli/mcp/installer.js

CriticalSecret Patterncli/errors/errors.spec.js

HighInstall Time Lifecycle Scriptspackage.json

HighChild Processcli/audit-preflight-git.js

HighShellcli/build/executor.js

HighSame File Env Network Executioncli/license.js

HighTrigger Reachable External Ai Agent Control Surface Mutationcli/pillars-wizard.js

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumNetwork

MediumEnvironment Vars

MediumShips Build Helperscripts/pre-commit.sh

Affected versions and remediation

This report applies to @chem-x/create-chemx@26.9.20-1257.

See all versions of @chem-x/create-chemx for other recorded verdicts.

Avoid installing @chem-x/create-chemx@26.9.20-1257. Remove it from direct dependencies and check your lockfile for transitive copies.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.
If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.

Evidence last updated: 2026-10-12 06:05:46.762Z (UTC).

Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.

AI Security Review

Decision evidence

Source & flagged code

Source & flagged code

Findings

Affected versions and remediation

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Behavioral surface

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Source & flagged code