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 OSPF implementation in Cisco IOS 12.0 through 12.4 and 15.0 through 15.3, IOS-XE 2.x through 3.9.xS, ASA and PIX 7.x through 9.1, FWSM, NX-OS, and StarOS before 14.0.50488 does not properly validate Link State Advertisement (LSA) type 1 packets before performing operations on the LSA database, which allows remote attackers to cause a denial of service (routing disruption) or obtain sensitive packet information via a (1) unicast or (2) multicast packet, aka Bug IDs CSCug34485, CSCug34469, CSCug39762, CSCug63304, and CSCug39795.

The ipv6 component in Cisco IOS before 15.1(4)M1.3 allows remote attackers to conduct fingerprinting attacks and obtain potentially sensitive information about the presence of the IOS operating system via an ICMPv6 Echo Request packet containing a Hop-by-Hop (HBH) extension header (EH) with a 0x0c01050c value in the PadN option data, aka Bug ID CSCtq02219.

The provider-edge MPLS NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload) via a malformed SIP packet to UDP port 5060, aka Bug ID CSCti98219.

The NAT implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 3.1.xSG, allows remote attackers to cause a denial of service (device reload or hang) via malformed NetMeeting Directory (aka Internet Locator Service or ILS) LDAP traffic, aka Bug ID CSCtd10712.

The Neighbor Discovery (ND) protocol implementation in Cisco IOS on unspecified switches allows remote attackers to bypass the Router Advertisement Guarding functionality via a fragmented IPv6 packet in which the Router Advertisement (RA) message is contained in the second fragment, as demonstrated by (1) a packet in which the first fragment contains a long Destination Options extension header or (2) a packet in which the first fragment contains an ICMPv6 Echo Request message.

STCAPP (aka the SCCP telephony control application) on Cisco IOS before 15.0(1)XA1 does not properly handle multiple calls to a shared line, which allows remote attackers to cause a denial of service (port hang) by simultaneously ending two calls that were controlled by CallManager Express (CME), aka Bug ID CSCtd42552.

CallManager Express (CME) on Cisco IOS before 15.0(1)XA1 does not properly handle SIP TRUNK traffic that contains rate bursts and a "peculiar" request size, which allows remote attackers to cause a denial of service (memory consumption) by sending this traffic over a long duration, aka Bug ID CSCtb47950.

Cisco IOS before 15.0(1)XA1 does not clear the public key cache upon a change to a certificate map, which allows remote authenticated users to bypass a certificate ban by connecting with a banned certificate that had previously been valid, aka Bug ID CSCta79031.

Cisco IOS before 15.0(1)XA1, when certain TFTP debugging is enabled, allows remote attackers to cause a denial of service (device crash) via a TFTP copy over IPv6, aka Bug ID CSCtb28877.

Memory leak in Cisco IOS before 15.0(1)XA5 might allow remote attackers to cause a denial of service (memory consumption) by sending a crafted SIP REGISTER message over UDP, aka Bug ID CSCtg41733.

CallManager Express (CME) on Cisco IOS before 15.0(1)XA allows remote authenticated users to cause a denial of service (device crash) by using an extension mobility (EM) phone to interact with the menu for SNR number changes, aka Bug ID CSCta63555.

Memory leak in the gk_circuit_info_do_in_acf function in the H.323 implementation in Cisco IOS before 15.0(1)XA allows remote attackers to cause a denial of service (memory consumption) via a large number of calls over a long duration, as demonstrated by InterZone Clear Token (IZCT) test traffic, aka Bug ID CSCsz72535.

Cisco IOS before 15.0(1)XA does not properly handle IRC traffic during a specific time period after an initial reload, which allows remote attackers to cause a denial of service (device reload) via an attempted connection to a certain IRC server, related to a "corrupted magic value," aka Bug ID CSCso05336.

The Neighbor Discovery (ND) protocol implementation in the IPv6 stack in Cisco IOS before 15.0(1)XA5 allows remote attackers to cause a denial of service (CPU consumption and device hang) by sending many Router Advertisement (RA) messages with different source addresses, as demonstrated by the flood_router6 program in the thc-ipv6 package, aka Bug ID CSCti33534.

The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

The virtual private dial-up network (VPDN) component in Cisco IOS before 12.3 allows remote attackers to cause a denial of service (resource exhaustion) via a series of PPTP sessions, related to the persistence of interface descriptor block (IDB) data structures after process termination, aka bug ID CSCdv59309.