Netgate pfSense CE through 2.9.0 contains a newline injection vulnerability in services_pppoe_edit.php that allows privileged users to inject mpd.secret entries via unvalidated username POST fields. Attackers with the PPPoE Server Edit privilege can add a line whose secret begins with '!', making mpd5 run commands as root when a PPPoE client authenticates.

Netgate pfSense CE through 2.9.0 contains a newline injection vulnerability in services_pppoe_edit.php that allows privileged users to inject mpd.secret entries via unvalidated username POST fields. Attackers with the PPPoE Server Edit privilege can add a line whose secret begins with '!', making mpd5 run commands as root when a PPPoE client authenticates.