registry / AI-agent control-surface risk / @chem-x/create-chemx / 26.10.4-235

@chem-x/create-chemx@26.10.4-235

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

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The package automatically changes consumer Cursor and VS Code MCP settings during postinstall, registering an AI-agent server without a separate consent step. This is an unconsented install-time mutation of an agent control surface, supporting a block under the stated policy.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

Installing the package in a consumer project with npm.

Impact

An AI-enabled editor may expose the configured MCP server to its agent.

Mechanism

The postinstall handler invokes the MCP installer, which writes a server entry into Cursor settings and can select an npm exec command when no local executable is found.

Policy narrative

An npm postinstall runs the MCP installer against the consumer directory. The installer creates or updates editor MCP configuration and registers a Chemical X server without a separate consent prompt. Its fallback command uses npm exec to invoke chemx mcp.

AI rationale

Evidence

package.jsoncli/postinstall.jscli/mcp/installer.jsconsumer .cursor/mcp.jsonconsumer .vscode/mcp.json

Decision evidence

public snapshot

AI identified this as a dangerous AI-agent capability at 94.0% confidence with low false-positive risk.

Evidence for policy risk

The package runs cli/postinstall.js automatically after installation.
The postinstall handler calls installAllMcpConfigs for the consumer directory without a consent check.
The MCP installer writes a chemical-x server entry into the consumer's Cursor configuration.
The server command may fall back to npm exec -y -- chemx mcp when no local executable is found.
The installer and wizard also contain the indicated agent-configuration code; the wizard writes files only when selected pillars exist and the operation is not a dry run.
The installer test verifies that the MCP configuration creates a chemical-x server entry.

Evidence against

The package's postinstall excludes installation into its own source directory.
The available excerpts show an MCP server setup, not credential collection or exfiltration.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStrings

Source & flagged code

11 flagged

package.jsonView file

Lines 33-73json

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 "bench": "node benchmarks/run-benchmark.mjs",

45 "ui": "node cli/index.js ui",

46 "dev:ui": "node cli/index.js ui --dev",

47 "dev:ui:watch": "node --watch --watch-path=cli cli/index.js ui --dev",

48 "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",

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

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

51 "typecheck": "tsc --noEmit",

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

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

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg · L53

Medium

Ambiguous Install Lifecycle Script

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

package.jsonView on unpkg · L53

54 "chemx:mcp": "chemx mcp",

55 "chemx:verify": "chemx verify",

56 "chemx:test": "chemx test",

57 "chemx:typecheck": "chemx typecheck"

58 },

59 "dependencies": {

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

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

62 "@babel/types": "^7.29.8"

63 },

64 "devDependencies": {

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

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

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

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

69 "chemx": "26.9.20-408",

70 "react": "^18.3.1",

71 "react-dom": "^18.3.1",

72 "typescript": "^5.9.3"

73 }

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 = 8215 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

scripts/pre-commit.shView on unpkg

cli/verify-lint.js#virtual:normalized:round1View file

•stage = ast_semantic_analysis; reason = ast_parse_error; limitedFiles = 1

High

Semantic Analysis Limited

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

cli/verify-lint.js#virtual:normalized:round1View on unpkg

Source & flagged code

11 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 Critical6 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

HighSemantic Analysis Limitedcli/verify-lint.js#virtual:normalized:round1

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumNetwork

Medium

Affected versions and remediation

This report applies to @chem-x/create-chemx@26.10.4-235.

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

Avoid installing @chem-x/create-chemx@26.10.4-235. 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 06:09:51.257Z (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