registry / @chemx/create-chemx / 26.9.28-276

@chemx/create-chemx@26.9.28-276

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 registers its own MCP server through a postinstall hook, creating an agent extension lifecycle risk. The inspected behavior does not establish credential theft, remote payload execution, or broader agent control manipulation, so a publish block is not supported.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

Installing the package with npm runs its postinstall hook.

Impact

The IDE can expose this package’s MCP tools to its agent after installation.

Mechanism

The hook invokes the MCP installer, which adds a Chemical X server entry to project or Antigravity MCP 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 called this Suspicious at 88.0% confidence as Dangerous Capability with medium false-positive risk.

Evidence for warning

package.json defines a postinstall hook that runs cli/postinstall.js.
The postinstall handler targets the installing project and calls the MCP configuration installer without a consent prompt.
The installer writes a package-owned MCP server entry to Cursor and VS Code project configuration and also attempts Antigravity configuration.
The installer resolves the server to this package’s local CLI when available, otherwise to the Chemx CLI through npm exec.
Other agent steering changes are exposed through explicit installer choices or the pillars wizard, so they do not establish a separate install-time attack.

Evidence against

The install-time behavior sets up this package’s own MCP server; inspected source does not show a remote payload, credential forwarding, or unrelated configuration command.
The flagged installer-spec and pillars-wizard locations concern MCP setup coverage and explicit wizard behavior, respectively.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystem

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 = 5153 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 @chemx/create-chemx@26.9.28-276.

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

Review the evidence and your use of @chemx/create-chemx@26.9.28-276 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: 2026-10-12 06:47:51.083Z (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

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Behavioral surface

Related packages

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Source & flagged code