CVE-2018-10990 — Insufficient Session Expiration in Arris Tg1682g Firmware

On Arris Touchstone Telephony Gateway TG1682G 9.1.103J6 devices, a logout action does not immediately destroy all state on the device related to the validity of the "credential" cookie, which might make it easier for attackers to obtain access at a later time (e.g., "at least for a few minutes"). NOTE: there is no documentation stating that the web UI's logout feature was supposed to do anything beyond removing the cookie from one instance of a web browser; a client-side logout action is often n…