mev-shield

MAL-2026-4609

Malicious code in mev-shield (npm)

Details


---
_-= Per source details. Do not edit below this line.=-_

## Source: amazon-inspector (9783d5e48d62da6de516b1cf5d36474143528a9c6f33a86892ee558266a4e5ec)
The package advertises itself as an 'MEV protection layer for Ethereum trading bots' but does the opposite. On `npm install`, a postinstall script base64-decodes the URL `http://165.22.200.211:8545` (an attacker-controlled Ethereum JSON-RPC endpoint, labeled 'honeypot RPC' in the package's own comments) and writes it into the installer's `.env` across multiple RPC variables (ETHEREUM_RPC, ETH_RPC, WEB3_RPC, RPC_ENDPOINT). On `require()`, `config-manager.js` further mutates the consumer's project files in place: it prepends `RPC_URL=http://165.22.200.211:8545` to scripts in `package.json`, injects the same env entry into `docker-compose.yml`, and rewrites `rpc_url` fields in any `config.json` / `bot-config.json` / `settings.json` / `config/trading.json` it finds in the working directory. An `optimizeRPC()` 'benchmark' is rigged so the attacker IP always wins regardless of measured latency (`// THE MAGIC: Our honeypot always "wins"`). Persistence is layered on top: a `preuninstall` keepalive script intentionally leaves the honeypot RPC in `.env` after the package is removed, and a `git-hooks.js` module installs a `.git/hooks/pre-commit` hook that re-executes `node -e "require('mev-shield');"` on every commit to re-inject the malicious RPC if it has been cleaned up. The postinstall payload is deliberately obfuscated with base64 and `_0x`-prefixed identifiers, with a self-incriminating comment 'Obfuscated module loader - makes static analysis harder'. Net effect on installers: every pending Ethereum transaction submitted by the consumer's trading bot is routed through the attacker, enabling frontrunning and sandwich attacks against the installer's funds, and the redirection survives uninstall.

Compromised versions (1)

1.4.2

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.