Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers.
The DCERPC inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.3 before 8.3(2.25), 8.4 before 8.4(2.5), and 8.5 before 8.5(1.13) and the Firewall Services Module (FWSM) 4.1 before 4.1(7) in Cisco Catalyst 6500 series switches and 7600 series routers allows remote attackers to cause a denial of service (device reload) via a crafted DCERPC packet, aka Bug IDs CSCtr21346 and CSCtr27521.
Stack-based buffer overflow in the DCERPC inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.3 before 8.3(2.34), 8.4 before 8.4(4.4), 8.5 before 8.5(1.13), and 8.6 before 8.6(1.3) and the Firewall Services Module (FWSM) 4.1 before 4.1(9) in Cisco Catalyst 6500 series switches and 7600 series routers might allow remote attackers to execute arbitrary code via a crafted DCERPC packet, aka Bug IDs CSCtr21359 and CSCtr27522.
The DHCP server on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 7.0 before 7.2(5.8), 7.1 before 7.2(5.8), 7.2 before 7.2(5.8), 8.0 before 8.0(5.28), 8.1 before 8.1(2.56), 8.2 before 8.2(5.27), 8.3 before 8.3(2.31), 8.4 before 8.4(3.10), 8.5 before 8.5(1.9), and 8.6 before 8.6(1.5) does not properly allocate memory for DHCP packets, which allows remote attackers to cause a denial of service (device reload) via a series of crafted IPv4 packets, aka Bug ID CSCtw84068.
The DCERPC inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.3 before 8.3(2.25), 8.4 before 8.4(2.5), and 8.5 before 8.5(1.13) and the Firewall Services Module (FWSM) 4.1 before 4.1(7) in Cisco Catalyst 6500 series switches and 7600 series routers allows remote attackers to cause a denial of service (device reload) via a crafted DCERPC packet, aka Bug IDs CSCtr21376 and CSCtr27524.
The SIP inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.2 before 8.2(5.17), 8.3 before 8.3(2.28), 8.4 before 8.4(2.13), 8.5 before 8.5(1.4), and 8.6 before 8.6(1.5) allows remote attackers to cause a denial of service (device reload) via a crafted SIP media-update packet, aka Bug ID CSCtr63728.
The AAA functionality in the IPv4 SSL VPN implementations on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.2 before 8.2(5.30) and 8.3 before 8.3(2.34) allows remote attackers to cause a denial of service (device reload) via a crafted authentication response, aka Bug ID CSCtz04566.
The Threat Detection feature on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.0 through 8.2 before 8.2(5.20), 8.3 before 8.3(2.29), 8.4 before 8.4(3), 8.5 before 8.5(1.6), and 8.6 before 8.6(1.1) allows remote attackers to cause a denial of service (device reload) via (1) IPv4 or (2) IPv6 packets that trigger a shun event, aka Bug ID CSCtw35765.
Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 7.0 through 7.2 before 7.2(5.7), 8.0 before 8.0(5.27), 8.1 before 8.1(2.53), 8.2 before 8.2(5.8), 8.3 before 8.3(2.25), 8.4 before 8.4(2.5), and 8.5 before 8.5(1.2) and the Firewall Services Module (FWSM) 3.1 and 3.2 before 3.2(23) and 4.0 and 4.1 before 4.1(8) in Cisco Catalyst 6500 series devices, when multicast routing is enabled, allow remote attackers to cause a denial of service (device reload) via a crafted IPv4 PIM message, aka Bug IDs CSCtr47517 and CSCtu97367.
The UDP inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.0 before 8.0(5.25), 8.1 before 8.1(2.50), 8.2 before 8.2(5.5), 8.3 before 8.3(2.22), 8.4 before 8.4(2.1), and 8.5 before 8.5(1.2) does not properly handle flows, which allows remote attackers to cause a denial of service (device reload) via a crafted series of (1) IPv4 or (2) IPv6 UDP packets, aka Bug ID CSCtq10441.
Cisco Adaptive Security Appliances (ASA) 5500 series devices, and the ASA Services Module (ASASM) in Cisco Catalyst 6500 series devices, with software 8.4 before 8.4(2.11) and 8.5 before 8.5(1.4) allow remote attackers to cause a denial of service (device reload) via (1) IPv4 or (2) IPv6 packets that trigger syslog message 305006, aka Bug ID CSCts39634.