TP-Link Archer AX21 tmpServer Command 0x422 Stack-based Buffer Overflow Remote Code Execution Vulnerability

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link Archer AX21 routers. Authentication is required to exploit this vulnerability. The specific flaw exists within the handling of command 0x422 provided to the tmpServer service. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root.