registry / AI-agent control-surface risk / chemx / 26.9.20-1298

chemx@26.9.20-1298

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

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The automatic postinstall path writes behavior-bearing MCP configuration for supported consumer agent clients without a consent check. This is a concrete install-time control-surface mutation, so the package meets the block policy.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

Installing the package through npm, which runs its postinstall hook.

Impact

The configured agent clients gain a registered Chemical X MCP server that can be invoked from those clients.

Mechanism

The hook resolves the consumer project and calls the MCP installer, which writes the package's server entry into supported agent configuration files.

Policy narrative

On package installation, the postinstall hook resolves the consumer project directory and automatically calls the MCP configuration installer. The installer adds a Chemical X server entry to consumer agent configuration, including Cursor and VS Code, and can also update Antigravity configuration. No consent guard appears on this install-time path, so this qualifies as unconsented lifecycle mutation of AI-agent control surfaces.

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 96.0% confidence with low false-positive risk.

Evidence for policy risk

package.json runs cli/postinstall.js automatically during installation.
The postinstall targets the consuming project and calls installAllMcpConfigs without a consent check.
That installer writes MCP configuration into the consumer's Cursor and VS Code directories; its full routine also invokes Antigravity configuration setup.
The MCP configuration registers a Chemical X server, enabling it in supported agent clients.
The wizard and installer target locations concern separate agent configuration behavior; the install hook itself is sufficient to establish the automatic mutation.

Evidence against

The project wizard offers a choice to skip agent steering, but that choice does not guard the separate postinstall MCP configuration.
The installer merges the Chemical X server entry into existing MCP configuration rather than replacing other servers.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

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

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 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 chemx@26.9.20-1298.

See all versions of chemx for other recorded verdicts.

Avoid installing chemx@26.9.20-1298. 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 06:57:27.938Z (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

Other AI-agent control-surface risk packages

Behavioral surface

Related packages

Other AI-agent control-surface risk packages

Source & flagged code