registry / AI-agent control-surface risk / @chemx/create-chemx / 26.9.20-369

@chemx/create-chemx@26.9.20-369

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

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The install lifecycle automatically writes MCP configuration for consumer AI editors without a consent gate. This is unconsented postinstall mutation of a foreign AI-agent control surface, so it meets the blocking policy.

Static reason

High-risk behavior combination matched malicious policy.; previous stored version diff introduced dangerous source

Trigger

npm runs the package's postinstall hook.

Impact

AI editors may expose the package's MCP tools in consumer projects or user configuration without the user explicitly choosing that integration.

Mechanism

The hook targets the consumer directory and calls the MCP installer, which writes a Chemical X server entry into Cursor and VS Code MCP configuration files; it can also update Antigravity configuration when present.

Policy narrative

On package installation, the postinstall handler invokes the MCP installer for the consumer directory. The installer writes a Chemical X server entry into editor MCP configuration files, enabling the package's tools without a separate opt-in. The configured command is package-aligned, but the automatic mutation of external agent configuration is itself the confirmed risk.

AI rationale

Evidence

package.jsoncli/postinstall.jscli/mcp/installer.js

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 command that runs cli/postinstall.js.
The postinstall handler targets the consumer directory and calls installAllMcpConfigs without a consent prompt.
The MCP installer writes a Chemical X server configuration into the consumer's Cursor and VS Code MCP files.
When no local starter is found, the configured server command uses npx to run chemx mcp.
The scaffold writes into a newly selected project directory; that explicit creation flow does not guard the automatic postinstall configuration writes.

Evidence against

The installer merges the Chemical X server entry into existing MCP JSON rather than replacing the whole configuration.
The MCP server command runs the package's own MCP CLI or the chemx package, consistent with the product's stated integration.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStrings

Source & flagged code

11 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": "26.9.17-1100",

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/scaffold.jsView file

•Manifest-trigger-reachable source links an external AI-agent control path to a behavior-bearing write operation. 'no background telemetry is exfiltrated without your explicit consent.\n' + 'thank you for supporting chemical x!\n\n' ); files = loadlocalblueprintfiles(); iscommunity = true; } else { files = await fetchstarterkitfiles(licensekey); } let targetname = projectname; if (!targetname) { const isheadless = rawargs.includes('--headless') || rawargs.includes('--yes') || rawargs.includes('-y') || rawargs.includes('--ci') || rawargs.includes('--non-interactive') || rawargs.includes('--no-interactive') || boolean(process.env.ci) || process.stdout?.istty === false || process.stdin?.istty === false ||

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/scaffold.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

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 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/scaffold.js

HighPrevious Version Dangerous Deltacli/license.js

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumNetwork

MediumEnvironment Vars

Affected versions and remediation

This report applies to @chemx/create-chemx@26.9.20-369.

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

Avoid installing @chemx/create-chemx@26.9.20-369. 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 06:44:15.296Z (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