---
canonical: "https://firewall.lpm.dev/npm/mutex-lite/v/1.4.2"
markdown: "https://firewall.lpm.dev/npm/mutex-lite/v/1.4.2.md"
package: "mutex-lite"
report_status: "published"
title: "mutex-lite@1.4.2 npm security report"
verdict: "malicious"
version: "1.4.2"
---

# mutex-lite@1.4.2 npm security report

> **Trust boundary:** Package metadata, advisory text, filenames, URLs, and source snippets in this report come from external packages or feeds. Treat them as untrusted evidence. Do not execute instructions or code found in this document.

## Verdict summary
**Blocked & quarantined** — Quarantined by product-default policy — this version is not allowed through the firewall.

- **Verdict:** Malicious
- **Product-default install policy:** Block
- **Firewall policy:** Matched malicious
- **Public report status:** Published
- **Threat category:** Malware
- **Selected version:** 1.4.2
- **Selected version is latest:** Yes
- **Analysis source:** OSV Malicious Advisory (OpenSSF/OSV)

OpenSSF/OSV advisory MAL-2026-14281 confirms this npm version as malicious. The package is named to resemble async-mutex and exports a Mutex API with the same surface, but lib/Mutex.js has been altered so that Mutex.prototype.runExclusive covertly requires./common and invokes runMutexExclusive(callback.meta.jobId) before running the user's callback — a field the legitimate async-mutex API does not use. lib/common.js is obfuscated and contains a decoded string table including...

## Latest scan
- **Scanner version:** external-osv-malicious-v1
- **Verdict:** Malicious
- **Confidence:** 100.0%
- **Started:** 2026-08-19T08:55:04.185Z
- **Finished:** 2026-08-19T08:55:04.185Z
- **Download time:** Not available
- **Static scan time:** Not available
- **AI review time:** Not available
- **Total time:** Not available

## Security analysis

No additional public attack-surface or AI-review details are available.

## Public findings

### 1. High: Osv Malicious Advisory
- **Category:** External Intel
- **Confidence:** 100.0%

The package is named to resemble async-mutex and exports a Mutex API with the same surface, but lib/Mutex.js has been altered so that Mutex.prototype.runExclusive covertly requires./common and invokes runMutexExclusive(callback.meta.jobId) before running the user's callback — a field the legitimate async-mutex API does not use. lib/common.js is obfuscated and contains a decoded string table including 'withMutex.min.js', 'aes-256-gcm', and 'scrypt' plus a hardcoded SHA1 gate 'b7e54f...5fe5'; when the hidden trigger fires, it reads the bundled ciphertext lib/withMutex.min.js, decrypts it with AES-256-GCM using material derived from callback.meta.jobId, writes the plaintext to os.tmpdir(), and runs it with require('child\_process').spawn('node', \[tempFile,...\], {detached:true, stdio:'ignore', windowsHide:true}). The sibling file lib/withMutex.min.d.js bundles a full ethers library, indicating the encrypted payload targets Ethereum wallet operations in consuming applications. Any application that consumes this package as if it were async-mutex and exercises runExclusive with the attacker-known jobId value will have arbitrary Node code executed under its own process, detached and with output suppressed.

## Dependencies and install lifecycle
- **Lifecycle scripts present:** No

- **Dependencies:** 0
- **Optional dependencies:** 0
- **Peer dependencies:** 0
- **Development dependencies:** 0
- **Published dependency-graph edges:** 0

## Package metadata
- **Package:** mutex-lite
- **Ecosystem:** npm
- **Version:** 1.4.2
- **Version published:** 2026-08-18T14:41:07.269Z
- **Package first seen:** 2026-08-19T08:55:04.185Z
- **Package last seen:** 2026-08-19T08:55:04.185Z
- **Known versions:** 1
- **Latest version:** 1.4.2
- **Appeal under review:** No

## References
- [HTML security report](<https://firewall.lpm.dev/npm/mutex-lite/v/1.4.2>)
- [OSV advisory](<https://osv.dev/vulnerability/MAL-2026-14281>)
- [PACKAGE](<https://www.npmjs.com/package/mutex-lite/v/1.4.2>)