The SIP implementation in Cisco Unified Communications Manager (CUCM) 6.x and 7.x before 7.1(5b)su5, 8.x before 8.5(1)su4, and 8.6 before 8.6(2a)su1; Cisco IOS 12.2 through 12.4 and 15.0 through 15.2; and Cisco IOS XE 3.3.xSG before 3.3.1SG, 3.4.xS, and 3.5.xS allows remote attackers to cause a denial of service (service crash or device reload) via a crafted SIP message containing an SDP session description, aka Bug IDs CSCtw66721, CSCtj33003, and CSCtw84664.

The Intrusion Prevention System (IPS) feature in Cisco IOS 12.3 through 12.4 and 15.0 through 15.2, in certain configurations of enabled categories and missing signatures, allows remote attackers to cause a denial of service (device reload) via DNS packets, aka Bug ID CSCtw55976.

The DHCPv6 server in Cisco IOS 12.2 through 12.4 and 15.0 through 15.2 and IOS XE 2.1.x through 2.6.x, 3.1.xS before 3.1.4S, 3.1.xSG and 3.2.xSG before 3.2.5SG, 3.2.xS, 3.2.xXO, 3.3.xS, and 3.3.xSG before 3.3.1SG allows remote attackers to cause a denial of service (device reload) via a malformed DHCPv6 packet, aka Bug ID CSCto57723.

Cisco IOS 12.3 and 12.4 on Aironet access points allows remote attackers to cause a denial of service (radio-interface input-queue hang) via IAPP 0x3281 packets, aka Bug ID CSCtc12426.

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.

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.

Cisco IOS 12.0 through 12.4, when IP-based tunnels and the Cisco Express Forwarding feature are enabled, allows remote attackers to cause a denial of service (device reload) via a malformed packet that is not properly handled during switching from one tunnel to a second tunnel, aka Bug IDs CSCsh97579 and CSCsq31776.

Cisco IOS 12.0 through 12.4, when IP-based tunnels and the Cisco Express Forwarding feature are enabled, allows remote attackers to cause a denial of service (device reload) via malformed packets, aka Bug ID CSCsx70889.

The SSLVPN feature in Cisco IOS 12.3 through 12.4 allows remote attackers to cause a denial of service (device reload or hang) via a crafted HTTPS packet.

The (1) Cisco Unified Communications Manager Express; (2) SIP Gateway Signaling Support Over Transport Layer Security (TLS) Transport; (3) Secure Signaling and Media Encryption; (4) Blocks Extensible Exchange Protocol (BEEP); (5) Network Admission Control HTTP Authentication Proxy; (6) Per-user URL Redirect for EAPoUDP, Dot1x, and MAC Authentication Bypass; (7) Distributed Director with HTTP Redirects; and (8) TCP DNS features in Cisco IOS 12.0 through 12.4 do not properly handle IP sockets, which allows remote attackers to cause a denial of service (outage or resource consumption) via a series of crafted TCP packets.