registry / AI-agent control-surface risk / @chem-x/starter-kit / 26.9.16-1249

@chem-x/starter-kit@26.9.16-1249

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 modifies consumer AI-agent configuration by registering the package's MCP server without a consent check. This meets the policy for blocking unconsented lifecycle mutation of an agent control surface.

Static reason

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

Trigger

Installing the package with lifecycle scripts enabled.

Impact

Consumer agent configuration is changed automatically and may enable the package's MCP command in those tools.

Mechanism

The postinstall hook calls the MCP installer for the consumer project, which creates or merges Cursor MCP configuration; the installer also handles VS Code configuration and a project package script.

Policy narrative

During package installation, the postinstall hook invokes the MCP installer on the consumer project without a consent prompt. The installer writes agent configuration that registers the package's own MCP command. The inspected evidence establishes an unconsented install-time agent control surface change, but does not establish credential theft or exfiltration.

AI rationale

Evidence

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

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

The package runs cli/postinstall.js automatically after installation; that hook targets the consumer project and calls installAllMcpConfigs without a consent check.
The MCP installer creates or updates the consumer project's .cursor/mcp.json and writes the merged server configuration.
The agent query installer can append instructions to the consumer's AGENTS.md directing AI agents to use the package's search commands.
The MCP installer test exercises writing a Chemical X server entry to Cursor configuration.

Evidence against

The added MCP server is package-aligned and invokes this package's own CLI; the inspected evidence does not show credential collection or data exfiltration.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetworkShell

Supply chain

HighEntropyStringsUrlStrings

ManifestNo manifest risk signals triggered.

Source & flagged code

9 flagged

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

cli/terminal.jsView file

10} else if (platform === "win32") { L11: spawnSync("cmd.exe", ["/c", "start", '""', url], { stdio: "ignore", timeout: 3000 }); L12: } else {

High

Shell

Package source references shell execution.

cli/terminal.jsView on unpkg · L10

cli/license.jsView file

3import os from 'node:os'; L4: import { spawnSync } from 'node:child_process'; L5: import { ... L17: L18: export const API_BASE = process.env.CHEMICAL_X_API_URL || 'https://chemicalx.xophz.com'; L19: export const GATEKEEPER_API_URL = process.env.COMPASS_GATEKEEPER_URL || 'https://mycompassconsulting.com/wp-json/compass/v1/gatekeeper';

High

Same File Env Network Execution

A single source file combines environment access, network access, and code or shell execution; review context before blocking.

cli/license.jsView on unpkg · L3

cli/mcp/installer.jsView file

1Install-time code directly mutates a foreign AI-agent control surface: L17: export const mergeMcpServerConfig = (existingJsonString = '', serverDef = {}) => { L18: let parsed = { mcpServers: {} }; L19: ... L27: L28: const hasMcpServersObject = Boolean(parsed.mcpServers && typeof parsed.mcpServers === 'object'); L29: if (!hasMcpServersObject) { L30: parsed.mcpServers = {}; L31: } L32: L33: parsed.mcpServers[SERVER_KEY] = serverDef; L34: return JSON.stringify(parsed, null, 2) + '\n'; ... L87: const cursorDir = path.join(resolvedTarget, '.cursor'); Write operation from cli/mcp/installer.js: L17: export const mergeMcpServerConfig = (existingJsonString = '', serverDef = {}) => { L18: let parsed = { mcpServers: {} }; L19: ... L27: L28: const hasMcpServersObject = Boolean(parsed.mcpServers &

Critical

Ai Agent Control Hijack

Source creates an unconsented AI-agent control surface through install-time mutation or a default unauthenticated remote skill channel.

cli/mcp/installer.jsView on unpkg · L1

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 = @chem-x/starter-kit@26.9.14-1358 matchedIdentity = npm:QGNoZW0teC9zdGFydGVyLWtpdA: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

Source & flagged code

9 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 Critical6 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

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumNetwork

MediumEnvironment Vars

MediumShips Build Helperscripts/pre-commit.sh

MediumStructural Risk Force Deep Review

Low

Affected versions and remediation

This report applies to @chem-x/starter-kit@26.9.16-1249.

See all versions of @chem-x/starter-kit for other recorded verdicts.

Avoid installing @chem-x/starter-kit@26.9.16-1249. 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 05:54:57.933Z (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