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.

Cisco IOS 12.2 through 12.4 and 15.0 through 15.1, Cisco IOS XE 2.5.x and 2.6.x before 2.6.1, and Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.x before 6.1(5), 7.0 before 7.0(2a)su3, 7.1su before 7.1(3b)su2, 7.1 before 7.1(5), and 8.0 before 8.0(1) allow remote attackers to cause a denial of service (device reload or voice-services outage) via a SIP REFER request with an invalid Refer-To header, aka Bug IDs CSCta20040 and CSCta31358.

Cisco IOS 12.2 through 12.4 and 15.0 through 15.1, Cisco IOS XE 2.5.x and 2.6.x before 2.6.1, and Cisco Unified Communications Manager (aka CUCM, formerly CallManager) 6.x before 6.1(5)SU1, 7.x before 7.1(5), and 8.0 before 8.0(2) allow remote attackers to cause a denial of service (device reload or voice-services outage) via crafted SIP registration traffic over UDP, aka Bug IDs CSCtf72678 and CSCtf14987.

Unspecified vulnerability in the NAT for H.225.0 implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1 allows remote attackers to cause a denial of service (device reload) via transit traffic, aka Bug ID CSCtd86472.

Unspecified vulnerability in the NAT for H.323 implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1 allows remote attackers to cause a denial of service (device reload) via transit traffic, aka Bug ID CSCtf91428.

Unspecified vulnerability in the NAT for SIP implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1 allows remote attackers to cause a denial of service (device reload) via transit traffic on UDP port 5060, aka Bug ID CSCtf17624.

The IGMPv3 implementation in Cisco IOS 12.2, 12.3, 12.4, and 15.0 and IOS XE 2.5.x before 2.5.2, when PIM is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed IGMP packet, aka Bug ID CSCte14603.

Unspecified vulnerability in the H.323 implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 2.5.x before 2.5.2 and 2.6.x before 2.6.1, allows remote attackers to cause a denial of service (traceback and device reload) via crafted H.323 packets, aka Bug ID CSCtd33567.

Unspecified vulnerability in the H.323 implementation in Cisco IOS 12.1 through 12.4 and 15.0 through 15.1, and IOS XE 2.5.x before 2.5.2 and 2.6.x before 2.6.1, allows remote attackers to cause a denial of service (device reload) via crafted H.323 packets, aka Bug ID CSCtc73759.

Cisco IOS 12.1 through 12.4, when Cisco Unified Communications Manager Express (CME) or Cisco Unified Survivable Remote Site Telephony (SRST) is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed Skinny Client Control Protocol (SCCP) message, aka Bug ID CSCsz49741, the "SCCP Request Handling Denial of Service Vulnerability."

Cisco IOS 12.1 through 12.4, when Cisco Unified Communications Manager Express (CME) or Cisco Unified Survivable Remote Site Telephony (SRST) is enabled, allows remote attackers to cause a denial of service (device reload) via a malformed Skinny Client Control Protocol (SCCP) message, aka Bug ID CSCsz48614, the "SCCP Packet Processing Denial of Service Vulnerability."

Cisco IOS 12.1 through 12.4, and 15.0M before 15.0(1)M1, allows remote attackers to cause a denial of service (interface queue wedge) via malformed H.323 packets, aka Bug ID CSCta19962.

Unspecified vulnerability in the SIP implementation in Cisco IOS 12.3 and 12.4 allows remote attackers to execute arbitrary code via a malformed SIP message, aka Bug ID CSCsz89904, the "SIP Packet Parsing Arbitrary Code Execution Vulnerability."

Unspecified vulnerability in the SIP implementation in Cisco IOS 12.3 and 12.4 allows remote attackers to execute arbitrary code via a malformed SIP message, aka Bug ID CSCsz48680, the "SIP Message Processing Arbitrary Code Execution Vulnerability."

The SIP implementation in Cisco IOS 12.3 and 12.4 allows remote attackers to cause a denial of service (device reload) via a malformed SIP message, aka Bug ID CSCtb93416, the "SIP Message Handling Denial of Service Vulnerability."

Cisco IOS 12.2 through 12.4, when certain PMTUD, SNAT, or window-size configurations are used, allows remote attackers to cause a denial of service (infinite loop, and device reload or hang) via a TCP segment with crafted options, aka Bug ID CSCsz75186.

Unspecified vulnerability in Cisco IOS 12.0 through 12.4, IOS XE 2.1.x through 2.3.x before 2.3.2, and IOS XR 3.2.x through 3.4.3, when Multiprotocol Label Switching (MPLS) and Label Distribution Protocol (LDP) are enabled, allows remote attackers to cause a denial of service (device reload or process restart) via a crafted LDP packet, aka Bug IDs CSCsz45567 and CSCsj25893.