A vulnerability in the TCP socket code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a state condition between the socket state and the transmission control block (TCB) state. While this vulnerability potentially affects all TCP applications, the only affected application observed so far is the HTTP server. An attacker could exploit this vulnerability by sending specific HTTP requests at a sustained rate to a reachable IP address of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device.

A vulnerability in the ingress packet processing function of Cisco IOS Software for Cisco Catalyst 4000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper resource allocation when processing TCP packets directed to the device on specific Cisco Catalyst 4000 Series Switches. An attacker could exploit this vulnerability by sending crafted TCP streams to an affected device. A successful exploit could cause the affected device to run out of buffer resources, impairing operations of control plane and management plane protocols, resulting in a DoS condition. This vulnerability can be triggered only by traffic that is destined to an affected device and cannot be exploited using traffic that transits an affected device.