Loading npm security reports…

@costrict/csc@4.2.38: Malicious npm security report (Block) | LPM Firewall

registry / @costrict/csc / 4.2.38

@costrict/csc@4.2.38

costrict

AI Security Review

scanned 25d ago · by lpm-firewall-ai

Installing the package automatically registers a Chrome MCP integration and modifies broad Claude command directories. It also downloads and installs a native executable during postinstall.

Static reason

One or more suspicious static signals were detected.; source matched previously finalized malicious package; routed for review; source fingerprint signature matched known malicious package; routed for review

Trigger

npm or Bun installation of the package

Impact

A dependency installation can alter an external AI-agent control surface and delete user command resources without an explicit setup command.

Mechanism

Postinstall scripts invoke MCP registration, delete Claude command content, and fetch an executable.

Attack narrative

On installation, the manifest starts a parallel script launcher. That launcher invokes a Chrome MCP bridge with a register action and runs cleanup against the user's Claude command directory. The cleanup deletes matching command files and a prompts directory without an explicit user setup request. In the same install hook, the package downloads and installs an executable from external sources without a recorded integrity check.

AI rationale

This is unconsented postinstall mutation of a foreign AI-agent control surface, combined with broad deletion in the user's Claude command directory. The automatic native download further increases install-time supply-chain risk.

Evidence

package.jsonscripts/run-parallel.mjsscripts/setup-chrome-mcp.mjsscripts/cleanup-cosknow.mjsscripts/postinstall.cjs~/.claude/commands~/.costrict/commandsdist/vendor/ripgrep/<arch>-<platform>/rg

Source & flagged code

11 flagged · loading source

package.jsonView file

•scripts.postinstall = node scripts/run-parallel.mjs scripts/postinstall.cjs scripts/setup-chrome-mcp.mjs scripts/cleanup-cosknow.mjs

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

•scripts.postinstall = node scripts/run-parallel.mjs scripts/postinstall.cjs scripts/setup-chrome-mcp.mjs scripts/cleanup-cosknow.mjs

Medium

Ambiguous Install Lifecycle Script

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

package.jsonView on unpkg

scripts/postinstall.cjsView file

15require("fs") L16: const { spawn, spawnSync } = require("child_process") L17: const { setDefaultResultOrder } = require("node:dns") L18: const path = require("path") ... L32: const MIRROR_RELEASE_BASE = `https://ghproxy.net/https://github.com/microsoft/ripgrep-prebuilt/releases/download/v${RG_VERSION}` L33: const RELEASE_BASE = (process.env.RIPGREP_DOWNLOAD_BASE ?? DEFAULT_RELEASE_BASE).replace(/\/$/, "") L34: // costrict change: fallback to private registry when GitHub and ghproxy are both unreachable L35: const COSTRICT_PRIVATE_BASE = "https://shenma.sangfor.com.cn/costrict-cli/pkg/ripgrep" ... L42: function getPlatformMapping() { L43: const arch = process.arch L44: const platform = process.platform ... L119: // csc.ps1 before csc.cmd, and enterprise ExecutionPolicy often blocks .ps

High

Sandbox Evasion Gated Capability

Source gates dangerous network, credential, or execution behavior behind CI, host, platform, time, or geo fingerprint checks.

scripts/postinstall.cjsView on unpkg · L15

15require("fs") L16: const { spawn, spawnSync } = require("child_process") L17: const { setDefaultResultOrder } = require("node:dns") L18: const path = require("path") ... L32: const MIRROR_RELEASE_BASE = `https://ghproxy.net/https://github.com/microsoft/ripgrep-prebuilt/releases/download/v${RG_VERSION}` L33: const RELEASE_BASE = (process.env.RIPGREP_DOWNLOAD_BASE ?? DEFAULT_RELEASE_BASE).replace(/\/$/, "") L34: // costrict change: fallback to private registry when GitHub and ghproxy are both unreachable L35: const COSTRICT_PRIVATE_BASE = "https://shenma.sangfor.com.cn/costrict-cli/pkg/ripgrep" ... L42: function getPlatformMapping() { L43: const arch = process.arch L44: const platform = process.platform ... L119: // csc.ps1 before csc.cmd, and enterprise ExecutionPolicy often blocks .ps

High

Install Named Payload File

Install-named source file stages remote content through filesystem writes and execution.

scripts/postinstall.cjsView on unpkg · L15

•matchType = normalized_sha256 matchedPackage = @costrict/csc@4.2.36 matchedPath = scripts/postinstall.cjs matchedIdentity = npm:QGNvc3RyaWN0L2NzYw:4.2.36 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

scripts/postinstall.cjsView on unpkg

•matchType = malicious_source_fingerprint_signature signature = 40e856b5d6201563 signatureType = suspicious_hashes sourceLabel = final_verdict:malicious matchedPackage = @costrict/csc@4.2.36 matchedPath = scripts/postinstall.cjs matchedIdentity = npm:QGNvc3RyaWN0L2NzYw:4.2.36 similarity = 1.000 shingleOverlap = 5 summary = package final verdict is malicious

High

Known Malware Source Fingerprint Signature

Source fingerprint signature matches a known malicious package signature; route for source-aware review.

scripts/postinstall.cjsView on unpkg

scripts/setup-chrome-mcp.mjsView file

•Runtime or CLI code links a write operation to an explicit external AI-agent control path: #!/usr/bin/env node import { execfilesync } from 'node:child_process' import { mkdirsync } from 'node:fs' import { createrequire } from 'node:module' import { homedir } from 'node:os' import { join } from 'node:path' if (process.env.claude_code_skip_chrome_mcp_setup === '1') { process.exit(0) } const require = createrequire(import.meta.url) const clipath = require.resolve( '@claude-code-best/mcp-chrome-bridge/dist/cli.js', ) const userargs = process.argv.

High

External Ai Agent Control Surface Mutation

Runtime or CLI source writes behavior-bearing configuration into a user or project AI-agent control surface.

scripts/setup-chrome-mcp.mjsView on unpkg

dist/vendor/audio-capture/x64-darwin/audio-capture.nodeView file

•path = dist/vendor/audio-capture/x64-darwin/audio-capture.node kind = native_binary sizeBytes = 439076 magicHex = [redacted]

Medium

Ships Native Binary

Package ships native binary artifacts.

dist/vendor/audio-capture/x64-darwin/audio-capture.nodeView on unpkg

dist/cli.jsView file

•path = dist/cli.js kind = oversized_source_file sizeBytes = 36481078 magicHex = [redacted]

Medium

Oversized Source File

Package contains source files above the normal full-analysis size ceiling.

dist/cli.jsView on unpkg

•path = dist/cli.js kind = oversized_cli_entrypoint sizeBytes = 36481078 magicHex = [redacted]

Medium

Oversized Cli Entrypoint

Package contains an oversized executable-looking CLI entrypoint.

dist/cli.jsView on unpkg

dist/cli-node.jsView file

•matchType = normalized_sha256 matchedPackage = @costrict/csc@4.2.36 matchedPath = dist/cli-node.js matchedIdentity = npm:QGNvc3RyaWN0L2NzYw:4.2.36 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

dist/cli-node.jsView on unpkg

Source & flagged code

11 flagged

package.jsonView file

Lines 57-97json

57 "build:binary:all": "bun run build && bun run compile:linux && bun run compile:linux-baseline && bun run compile:linux-musl && bun run compile:linux-musl-baseline && bun run compile:win && bun run compile:win-baseline && bun run compile:mac-arm64 && bun run compile:mac-x64 && bun run compile:mac-x64-baseline",

58 "compile:linux": "bun build dist/cli.js --compile --target=bun-linux-x64 --outfile dist/csc-linux-x64",

59 "compile:linux-baseline": "bun build dist/cli.js --compile --target=bun-linux-x64-baseline --outfile dist/csc-linux-x64-baseline",

60 "compile:linux-musl": "bun build dist/cli.js --compile --target=bun-linux-x64-musl --outfile dist/csc-linux-x64-musl",

61 "compile:linux-musl-baseline": "bun build dist/cli.js --compile --target=bun-linux-x64-musl-baseline --outfile dist/csc-linux-x64-musl-baseline",

62 "compile:win": "bun build dist/cli.js --compile --target=bun-windows-x64 --outfile dist/csc-windows-x64.exe",

63 "compile:win-baseline": "bun build dist/cli.js --compile --target=bun-windows-x64-baseline --outfile dist/csc-windows-x64-baseline.exe",

64 "compile:mac-arm64": "bun build dist/cli.js --compile --target=bun-darwin-arm64 --outfile dist/csc-darwin-arm64",

65 "compile:mac-x64": "bun build dist/cli.js --compile --target=bun-darwin-x64 --outfile dist/csc-darwin-x64",

66 "compile:mac-x64-baseline": "bun build dist/cli.js --compile --target=bun-darwin-x64-baseline --outfile dist/csc-darwin-x64-baseline",

67 "dev": "bun run scripts/dev.ts",

68 "dev:inspect": "bun run scripts/dev-debug.ts",

69 "prepublishOnly": "bun run security:scan && bun run build",

70 "lint": "biome lint src/",

71 "lint:fix": "biome lint --fix src/",

72 "format": "biome format --write src/",

73 "prepare": "git config core.hooksPath .githooks",

74 "test": "bun test",

75 "check:unused": "knip-bun",

76 "health": "bun run scripts/health-check.ts",

77 "postinstall": "node scripts/run-parallel.mjs scripts/postinstall.cjs scripts/setup-chrome-mcp.mjs scripts/cleanup-cosknow.mjs",

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg · L77

Medium

Ambiguous Install Lifecycle Script

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

package.jsonView on unpkg · L77

78 "docs:dev": "npx mintlify dev",

79 "typecheck": "tsc --noEmit",

80 "rcs": "bun run scripts/rcs.ts",

81 "self-verify": "bun run scripts/self-verify.ts",

82 "security:scan": "bun run scripts/security-scan.ts"

83 },

84 "dependencies": {

85 "@agentclientprotocol/sdk": "^0.19.2",

86 "@anthropic-ai/sandbox-runtime": "^0.0.54",

87 "@claude-code-best/mcp-chrome-bridge": "^2.0.9",

88 "@protobufjs/utf8": "1.1.1",

89 "baseline-browser-mapping": "2.10.29",

90 "gray-matter": "^4.0.3",

91 "hono": "^4.12.26",

92 "partial-json": "^0.1.7",

93 "pngjs": "5.0.0",

94 "semver": "^7.8.4",

95 "undici": "^7.29.0",

96 "ws": "^8.21.0"

97 },

scripts/postinstall.cjsView file

Lines 1-35javascript

1#!/usr/bin/env node

2/**

3 * Postinstall script — runs automatically after `bun install` or `npm install`.

4 *

5 * Downloads ripgrep binary (idempotent, skips if exists).

6 * Works in dev mode (src/ exists), published mode (dist/ exists), with bun or node.

7 *

8 * Usage:

9 * node scripts/postinstall.js

10 * node scripts/postinstall.js --force

11 * bun run scripts/postinstall.js

scripts/setup-chrome-mcp.mjsView file

•Runtime or CLI code links a write operation to an explicit external AI-agent control path: #!/usr/bin/env node import { execfilesync } from 'node:child_process' import { mkdirsync } from 'node:fs' import { createrequire } from 'node:module' import { homedir } from 'node:os' import { join } from 'node:path' if (process.env.claude_code_skip_chrome_mcp_setup === '1') { process.exit(0) } const require = createrequire(import.meta.url) const clipath = require.resolve( '@claude-code-best/mcp-chrome-bridge/dist/cli.js', ) const userargs = process.argv.

High

External Ai Agent Control Surface Mutation

Runtime or CLI source writes behavior-bearing configuration into a user or project AI-agent control surface.

scripts/setup-chrome-mcp.mjsView on unpkg

dist/vendor/audio-capture/x64-darwin/audio-capture.nodeView file

•path = dist/vendor/audio-capture/x64-darwin/audio-capture.node kind = native_binary sizeBytes = 439076 magicHex = [redacted]

Medium

Ships Native Binary

Package ships native binary artifacts.

dist/vendor/audio-capture/x64-darwin/audio-capture.nodeView on unpkg

dist/cli.jsView file

•path = dist/cli.js kind = oversized_source_file sizeBytes = 36481078 magicHex = [redacted]

Medium

Oversized Source File

Package contains source files above the normal full-analysis size ceiling.

dist/cli.jsView on unpkg

•path = dist/cli.js kind = oversized_cli_entrypoint sizeBytes = 36481078 magicHex = [redacted]

Medium

Oversized Cli Entrypoint

Package contains an oversized executable-looking CLI entrypoint.

dist/cli.jsView on unpkg

dist/cli-node.jsView file

•matchType = normalized_sha256 matchedPackage = @costrict/csc@4.2.36 matchedPath = dist/cli-node.js matchedIdentity = npm:QGNvc3RyaWN0L2NzYw:4.2.36 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

dist/cli-node.jsView on unpkg