Cisco IOS before 15.1(1)SY1 allows remote authenticated users to cause a denial of service (device reload) by establishing a VPN session and then sending malformed IKEv2 packets, aka Bug ID CSCub39268.

The Flex-VPN load-balancing feature in the ipsec-ikev2 implementation in Cisco IOS before 15.1(1)SY3 does not require authentication, which allows remote attackers to trigger the forwarding of VPN traffic to an attacker-controlled destination, or the discarding of this traffic, by arranging for an arbitrary device to become a cluster member, aka Bug ID CSCub93641.

The ios-authproxy implementation in Cisco IOS before 15.1(1)SY3 allows remote attackers to cause a denial of service (webauth and HTTP service outage) via vectors that trigger incorrectly terminated HTTP sessions, aka Bug ID CSCtz99447.

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 packet driver in Cisco IOS allows remote attackers to cause a denial of service (device reload) via a series of (1) Virtual Switching Systems (VSS) or (2) Bidirectional Forwarding Detection (BFD) packets, aka Bug IDs CSCug41049 and CSCue61890.

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 IP Device Tracking (IPDT) feature in Cisco IOS and IOS XE allows remote attackers to cause a denial of service (IPDT AVL corruption and device reload) via a crafted sequence of ARP packets, aka Bug ID CSCuh38133.

The IPSec implementation in Cisco IOS allows remote attackers to cause a denial of service (MTU change and tunnel-session drop) via crafted ICMP packets, aka Bug ID CSCul29918.

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 IKEv2 implementation in Cisco IOS, when AES-GCM or AES-GMAC is used, allows remote attackers to bypass certain IPsec anti-replay features via IPsec tunnel traffic, aka Bug ID CSCuj47795.

Cisco IOS on Catalyst 3750X switches has default Service Module credentials, which makes it easier for local users to gain privileges via a Service Module login, aka Bug ID CSCue92286.

The OSPF functionality in Cisco IOS and IOS XE allows remote attackers to cause a denial of service (device reload) via crafted options in an LSA type 11 packet, aka Bug ID CSCui21030.

The remember feature in the DHCP server in Cisco IOS allows remote attackers to cause a denial of service (device reload) by acquiring a lease and then sending a DHCPRELEASE message, aka Bug ID CSCuh46822.

The TCP implementation in Cisco IOS does not properly implement the transitions from the ESTABLISHED state to the CLOSED state, which allows remote attackers to cause a denial of service (flood of ACK packets) via a crafted series of ACK and FIN packets, aka Bug ID CSCtz14399.

The default configuration of the Group Encrypted Transport VPN (GET VPN) feature on Cisco IOS uses an improper mechanism for enabling Group Domain of Interpretation (GDOI) traffic flow, which allows remote attackers to bypass the encryption policy via certain uses of UDP port 848, aka Bug ID CSCui07698.