A vulnerability in the web interface of Cisco TelePresence Conductor, Cisco Expressway Series, and Cisco TelePresence Video Communication Server (VCS) Software could allow an authenticated, remote attacker to trigger an HTTP request from an affected server to an arbitrary host. This type of attack is commonly referred to as server-side request forgery (SSRF). The vulnerability is due to insufficient access controls for the REST API of Cisco Expressway Series and Cisco TelePresence VCS. An attacker could exploit this vulnerability by submitting a crafted HTTP request to the affected server. Versions prior to XC4.3.4 are affected.

A flaw named SegmentSmack was found in the way the Linux kernel handled specially crafted TCP packets. A remote attacker could use this flaw to trigger time and calculation expensive calls to tcpcollapseofoqueue() and tcppruneofoqueue() functions by sending specially modified packets within ongoing TCP sessions which could lead to a CPU saturation and hence a denial of service on the system. Maintaining the denial of service condition requires continuous two-way TCP sessions to a reachable open port, thus the attacks cannot be performed using spoofed IP addresses.

A vulnerability in the cluster database (CDB) management component of Cisco Expressway Series Software and Cisco TelePresence Video Communication Server (VCS) Software could allow an authenticated, remote attacker to cause the CDB process on an affected system to restart unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to incomplete input validation of URL requests by the REST API of the affected software. An attacker could exploit this vulnerability by sending a crafted URL to the REST API of the affected software on an affected system. A successful exploit could allow the attacker to cause the CDB process on the affected system to restart unexpectedly, resulting in a temporary DoS condition. Cisco Bug IDs: CSCve77571.