Rooting a $10 TP-Link Router and Finding Credentials That Survive a Reset

Rooting, firmware analysis and persistent credentials of TP-Link TL-841N

A hands-on teardown of a TP-Link TL-841N router reveals an end-to-end hardware hacking workflow: locating UART pins, dumping firmware via UART and on-chip flash extraction, carving the flash dump into partitions, and analyzing the root filesystem. The author uncovers plaintext, hardcoded credentials from the previous owner, one of which persists even after a full factory reset—a serious security flaw.