registry / AI-agent control-surface risk / @chem-x/create-chemx / 26.9.21-227

@chem-x/create-chemx@26.9.21-227

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

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The manifest activates a postinstall hook that writes agent MCP configuration in the consumer project without a consent guard. That verified lifecycle mutation establishes an unconsented agent control-surface write, so this warrants blocking under the install-control-surface policy.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

npm installation runs the package's postinstall hook.

Impact

Affected agent clients can launch the registered Chemical X MCP server, and the configuration change persists after installation.

Mechanism

The hook targets the consumer directory and invokes the MCP installer, which writes Cursor and VS Code MCP configuration and may update Antigravity's global MCP configuration.

Policy narrative

The package's postinstall hook automatically installs MCP configuration in the consumer project. The installer registers its server for Cursor and VS Code and can also register it in an existing Antigravity configuration directory. This is an unconsented install-time change to agent control configuration.

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 91.0% confidence with low false-positive risk.

Evidence for policy risk

package.json runs cli/postinstall.js automatically after installation.
The postinstall hook targets the consumer directory and calls installAllMcpConfigs without a user consent check.
The MCP installer writes Cursor and VS Code project configuration to register the Chemical X server; it also registers Antigravity when its config directory exists.
The server registration uses a local CLI when available or runs npx -y chemx mcp otherwise.
The separate pillars wizard writes AGENTS.md and .cursorrules as an explicit setup path; it is not called by the postinstall hook.

Evidence against

The MCP installer merges the server entry into existing configuration rather than replacing the whole configuration object.
The postinstall hook skips installation when the target is the package's own directory.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStrings

Source & flagged code

10 flagged

package.jsonView file

Lines 29-69json

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 "check:frameworks": "node scripts/check-framework-generation.mjs",

46 "prepublishOnly": "node scripts/check-framework-generation.mjs",

47 "typecheck": "tsc --noEmit",

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

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

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg · L49

Medium

Ambiguous Install Lifecycle Script

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

package.jsonView on unpkg · L49

50 "chemx:mcp": "chemx mcp",

51 "chemx:verify": "chemx verify",

52 "chemx:test": "chemx test",

53 "chemx:typecheck": "chemx typecheck"

54 },

55 "dependencies": {

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

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

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

59 "react": "^18.3.1",

60 "react-dom": "^18.3.1"

61 },

62 "devDependencies": {

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

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

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

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

67 "chemx": "26.9.20-408",

68 "typescript": "^5.9.3"

69 }

cli/errors/errors.spec.jsView file

Lines 7-47javascript

7 maskSensitiveTokens,

8 normalizeHomePath,

9 sanitizeText,

10 sanitizeStackTrace

11} from './sanitizer.js';

12import {

13 buildIssueTitle,

14 buildIssueBody,

15 buildIssueWebUrl,

16 formatIssueContent

cli/audit-preflight-git.jsView file

Lines 1-21javascript

1import fs from 'node:fs';

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

High

Child Process

Package source references child process execution.

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

4const SOURCE_FILE_PATTERN = /

cli/build/executor.jsView file

Lines 1-31javascript

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

3export const executeBuild = (command, cwd = process.cwd(), options = {})

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

Lines 1-21javascript

1import fs from 'node:fs';

2import path from 'node:path';

3import os from 'node:os';

4import { syncAntigravityMcpSchemas } from './antigravity.js';

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 Medium5 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@26.9.21-227.

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

Avoid installing @chem-x/create-chemx@26.9.21-227. 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 06:06:53.530Z (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

Related packages

More from @chem-x

Other AI-agent control-surface risk packages

Behavioral surface

Related packages

More from @chem-x

Other AI-agent control-surface risk packages

Source & flagged code