MAL-2026-12437 Malicious code in simplipayng (npm)

dist/cjs/index.js appends an eval(atob(…)) blob to what appears to be a React Button re-export. The decoded payload queries public Ethereum RPCs for the latest transaction from the hardcoded address 0xa322E5f3D311D3080e6f0121063e9aDC2490Ef1a, extracts two IPv4 addresses encoded in the tx.to field, then fetches XOR-encoded next-stage JavaScript from those IPs over HTTP/HTTPS at the paths /0x/cls and /0x/ls and executes it via eval and spawn('node', ['-e',…], {detached:true}). Network and process sinks are hidden behind base64 wrapping and per-character \uXXXX unicode escapes for require('http'), require('https'), require('child_process'), and 'spawn'. Any project that require()s this package receives arbitrary remote code execution controlled by whoever writes to the on-chain dead-drop address, in a detached Node subprocess.

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.