registry / AI-agent control-surface risk / @chemx/create-chemx / 26.9.16-1408

@chemx/create-chemx@26.9.16-1408

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

AI Security Review

scanned 11d ago · by lpm-firewall-ai

The automatic install hook makes unconsented changes to consumer AI-agent configuration and supplies an MCP command for those clients. This meets the blocking policy for postinstall mutation of an agent control surface.

Static reason

High-risk behavior combination matched malicious policy.; previous stored version diff introduced dangerous source; source closely matched a different package identity

Trigger

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

Impact

The consumer's agent tools gain a newly configured server command that can run when the agent loads or uses the MCP configuration.

Mechanism

The hook writes project-level MCP configuration without a consent check, using a local command when available or npx -y chemx mcp otherwise.

Policy narrative

During npm installation, the postinstall hook targets the consumer project and configures Cursor and VS Code MCP settings without asking for consent. If no local ChemX entrypoint is found, the configuration uses npx -y chemx mcp, adding a package command to the agent's configured server set.

AI rationale

Evidence

package.jsoncli/postinstall.jscli/mcp/installer.js.cursor/mcp.json.vscode/mcp.json

Decision evidence

public snapshot

AI identified this as a dangerous AI-agent capability at 97.0% confidence with low false-positive risk.

Evidence for policy risk

The package manifest runs cli/postinstall.js automatically after installation.
The postinstall targets the installing project and calls installAllMcpConfigs without a consent prompt.
The installer creates and writes .cursor/mcp.json in the consumer project.
When no local ChemX entrypoint exists, the MCP config invokes npx -y chemx mcp.
The installer also configures .vscode/mcp.json; its test confirms the Cursor server entry is created.

Evidence against

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStringsUrlStrings

ManifestNo manifest risk signals triggered.

scanned 92 file(s), 601 KB of source, external domains: api.github.com, chemicalx.xophz.com, github.com, img.shields.io, mycompassconsulting.com, www.w3.org

Source & flagged code

10 flagged

package.jsonView file

Lines 32-71json

32 ".": "./cli/index.js",

33 "./audit": "./cli/audit.js",

34 "./build": "./cli/build.js",

35 "./search": "./cli/search.js",

36 "./mcp": "./cli/mcp/index.js",

37 "./reader": "./cli/reader.js",

38 "./patcher": "./cli/patcher.js"

39 },

40 "scripts": {

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

42 "test": "node --test cli/audit/*.spec.js cli/mcp/*.spec.js cli/*.spec.js",

43 "typecheck": "tsc --noEmit",

44 "create-capsule": "node cli/index.js",

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

46 "ci:audit": "node cli/index.js audit --ci --dir=cli",

47 "chemx": "node cli/index.js",

48 "q": "node cli/index.js q",

49 "search": "node cli/index.js search",

50 "mcp": "node cli/index.js mcp",

51 "install-mcp": "node cli/index.js install-mcp",

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

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg · L52

Medium

Ambiguous Install Lifecycle Script

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

package.jsonView on unpkg · L52

53 "read": "node cli/index.js read",

54 "patch": "node cli/index.js patch"

55 },

56 "dependencies": {

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

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

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

60 "react": "^18.3.1",

61 "react-dom": "^18.3.1"

62 },

63 "devDependencies": {

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

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

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

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

68 "typescript": "^5.9.3"

69 }

70}

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/terminal.jsView file

Lines 1-30javascript

1import readline from "node:readline";

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

3import { formatChemicalXGradient, ANSI } from "./theme.js";

5export const openBrowser

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';

5const SERVER_KEY =

cli/scaffold.jsView file

•Manifest-trigger-reachable source links an external AI-agent control path to a behavior-bearing write operation. import fs from 'node:fs'; import path from 'node:path'; import { hasgum, guminput, promptquestion, renderbanner } from './terminal.js'; import { obtainlicensekey, fetchstarterkitfiles, loadlocalblueprintfiles } from './license.js'; export const runscaffold = async (projectname, rawargs = [], onrunaudit = null) => { renderbanner('chemical x: molecular architecture scaffolder (npm create chemx)'); const licensekey = await obtainlicensekey(rawargs, onrunaudit); let iscommunity = false; let files = {}; if (!licensekey) { process.stdout.write( '\n\x1b[38;2;98;201;255m⚡ chemical x: community edition (free)\x1b[0m\n' + 'the community version is free because

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

•matchType = previous_version_dangerous_delta matchedPackage = @chemx/create-chemx@26.9.14-1358 matchedIdentity = npm:QGNoZW14L2NyZWF0ZS1jaGVteA:26.9.14-1358 similarity = 0.786 summary = stored previous version shares package body but lacks this dangerous source file

High

Previous Version Dangerous Delta

This package version adds a dangerous source file absent from the previous stored version; route for source-aware review.

scripts/pre-commit.shView on unpkg

•path = scripts/pre-commit.sh kind = build_helper sizeBytes = 4608 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

scripts/pre-commit.shView on unpkg

cli/audit/social-git.jsView file

•matchType = package_source_clone_identity_mismatch matchedPackage = create-chemx@26.9.14-1358 matchedPath = cli/audit/ai-slop-detector.js matchedIdentity = npm:Y3JlYXRlLWNoZW14:26.9.14-1358 similarity = 0.671 shingleOverlap = 47 summary = source files closely matched a different published package identity

High

Package Source Clone Identity Mismatch

Package source closely matches a different published package identity; review for dependency-confusion or copied-code abuse.

cli/audit/social-git.jsView 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/audit-preflight-git.jsView file

1import fs from 'node:fs'; L2: import { spawnSync } from 'node:child_process'; L3:

High

Child Process

Package source references child process execution.

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

Findings

1 Critical7 High5 Medium4 Low

CriticalAi Agent Control Hijackcli/mcp/installer.js

HighInstall Time Lifecycle Scriptspackage.json

HighChild Processcli/audit-preflight-git.js

HighShellcli/terminal.js

HighSame File Env Network Executioncli/license.js

HighTrigger Reachable External Ai Agent Control Surface Mutationcli/scaffold.js

HighPrevious Version Dangerous Deltascripts/pre-commit.sh

HighPackage Source Clone Identity Mismatchcli/audit/social-git.js

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumNetwork

MediumEnvironment Vars

MediumShips Build Helperscripts/pre-commit.sh

Affected versions and remediation

This report applies to @chemx/create-chemx@26.9.16-1408.

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

Avoid installing @chemx/create-chemx@26.9.16-1408. 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 06:43:36.985Z (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

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Source & flagged code