Cisco IOS before 15.1(2)SY allows remote authenticated users to cause a denial of service (device crash) by establishing an SSH session from a client and then placing this client into a (1) slow or (2) idle state, aka Bug ID CSCto87436.

Cisco IOS before 15.3(2)T, when scansafe is enabled, allows remote attackers to cause a denial of service (latency) via SYN packets that are not accompanied by SYN-ACK packets from the Scan Safe Tower, aka Bug ID CSCub85451.

Cisco IOS before 15.3(1)T on Cisco 2900 devices, when a VWIC2-2MFT-T1/E1 card is configured for TDM/HDLC mode, allows remote attackers to cause a denial of service (serial-interface outage) via certain Frame Relay traffic, aka Bug ID CSCub13317.

The IKE implementation in Cisco IOS 15.4(1)T and earlier and IOS XE allows remote attackers to cause a denial of service (security-association drop) via crafted Main Mode packets, aka Bug ID CSCun31021.

The Application Layer Gateway (ALG) module in Cisco IOS 12.2 through 12.4 and 15.0 through 15.4, when NAT is used, allows remote attackers to cause a denial of service (device reload) via crafted DNS packets, aka Bug ID CSCue00996.

The TCP Input module in Cisco IOS 12.2 through 12.4 and 15.0 through 15.4, when NAT is used, allows remote attackers to cause a denial of service (memory consumption or device reload) via crafted TCP packets, aka Bug IDs CSCuh33843 and CSCuj41494.

Cisco IOS 12.2 and 15.0 through 15.3 and IOS XE 3.2 through 3.7 before 3.7.5S and 3.8 through 3.10 before 3.10.1S allow remote attackers to cause a denial of service (device reload) via a malformed IKEv2 packet, aka Bug ID CSCui88426.

Cisco IOS 12.2 and 15.0 through 15.3, when used with the Kailash FPGA before 2.6 on RSP720-3C-10GE and RSP720-3CXL-10GE devices, allows remote attackers to cause a denial of service (route switch processor outage) via crafted IP packets, aka Bug ID CSCug84789.

Cisco IOS 15.1(2)SY3 and earlier, when used with Supervisor Engine 2T (aka Sup2T) on Catalyst 6500 devices, allows remote attackers to cause a denial of service (device crash) via crafted multicast packets, aka Bug ID CSCuf60783.

The MLDP implementation in Cisco IOS 15.3(3)S and earlier on 7600 routers, when many VRFs are configured, allows remote attackers to cause a denial of service (chunk corruption and device reload) by establishing many multicast flows, aka Bug ID CSCue22345.

The SSL VPN implementation in Cisco IOS 15.3(1)T2 and earlier allows remote authenticated users to cause a denial of service (interface queue wedge) via crafted DTLS packets in an SSL session, aka Bug IDs CSCuh97409 and CSCud90568.

Cisco IOS 12.4(24)MDB9 and earlier on Content Services Gateway (CSG) devices does not properly implement the "parse error drop" feature, which allows remote attackers to bypass intended access restrictions via a crafted series of packets, aka Bug ID CSCug90143.

The PPTP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via crafted TCP port-1723 packets, aka Bug ID CSCtq14817.

The DNS-over-TCP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via a crafted IPv4 DNS TCP stream, aka Bug ID CSCuf28733.

The DNS-over-TCP implementation in Cisco IOS 12.2 and 15.0 through 15.3, when NAT is used, allows remote attackers to cause a denial of service (device reload) via a crafted IPv4 DNS TCP stream, aka Bug ID CSCtn53730.

The T1/E1 driver-queue functionality in Cisco IOS 12.2 and 15.0 through 15.3, when an HDLC32 driver is used, allows remote attackers to cause a denial of service (interface queue wedge) via bursty network traffic, aka Bug ID CSCub67465.

Cisco IOS 12.2 through 12.4 and 15.0 through 15.3, and IOS XE 2.1 through 3.9, allows remote attackers to cause a denial of service (device reload) via crafted DHCP packets that are processed locally by a (1) server or (2) relay agent, aka Bug ID CSCug31561.

Race condition in the IPv6 virtual fragmentation reassembly (VFR) implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.3 allows remote attackers to cause a denial of service (device reload or hang) via fragmented IPv6 packets, aka Bug ID CSCud64812.

Memory leak in Cisco IOS 12.2, 15.1, and 15.2; IOS XE 3.4.2S through 3.4.5S; and IOS XE 3.6.xS before 3.6.1S allows remote attackers to cause a denial of service (memory consumption or device reload) via malformed IKEv1 packets, aka Bug ID CSCtx66011.

The NTP implementation in Cisco IOS 12.0 through 12.4 and 15.0 through 15.1, and IOS XE 2.1 through 3.3, does not properly handle encapsulation of multicast NTP packets within MSDP SA messages, which allows remote attackers to cause a denial of service (device reload) by leveraging an MSDP peer relationship, aka Bug ID CSCuc81226.