🛡️ MAL-2026-4609 — mev-shield

Malicious code in mev-shield (npm)

Source: amazon-inspector

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.

Source: ghsa-malware

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.