A vulnerability in the ISDN functions of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of specific values in the Q.931 information elements. An attacker could exploit this vulnerability by calling the affected device with specific Q.931 information elements being present. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device.

A vulnerability in the Hot Standby Router Protocol (HSRP) subsystem of Cisco IOS and IOS XE Software could allow an unauthenticated, adjacent attacker to receive potentially sensitive information from an affected device. The vulnerability is due to insufficient memory initialization. An attacker could exploit this vulnerability by receiving HSRPv2 traffic from an adjacent HSRP member. A successful exploit could allow the attacker to receive potentially sensitive information from the adjacent device.

A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability are due to a parsing issue on DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through routers that are running an affected version and have NBAR enabled. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

A vulnerability in the VLAN Trunking Protocol (VTP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to corrupt the internal VTP database on an affected device and cause a denial of service (DoS) condition. The vulnerability is due to a logic error in how the affected software handles a subset of VTP packets. An attacker could exploit this vulnerability by sending VTP packets in a sequence that triggers a timeout in the VTP message processing code of the affected software. A successful exploit could allow the attacker to impact the ability to create, modify, or delete VLANs and cause a DoS condition. There are workarounds that address this vulnerability. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS Software or Cisco IOS XE Software, are operating in VTP client mode or VTP server mode, and do not have a VTP domain name configured. The default configuration for Cisco devices that ar…

A vulnerability in the Cisco Network Plug and Play application of Cisco IOS 12.4 through 15.6 and Cisco IOS XE 3.3 through 16.4 could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data by using an invalid certificate. The vulnerability is due to insufficient certificate validation by the affected software. An attacker could exploit this vulnerability by supplying a crafted certificate to an affected device. A successful exploit could allow the attacker to conduct man-in-the-middle attacks to decrypt confidential information on user connections to the affected software. Cisco Bug IDs: CSCvc33171.

A vulnerability in motherboard console ports of line cards for Cisco ASR 1000 Series Aggregation Services Routers and Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, physical attacker to access an affected device's operating system. The vulnerability exists because an engineering console port is available on the motherboard of the affected line cards. An attacker could exploit this vulnerability by physically connecting to the console port on the line card. A successful exploit could allow the attacker to gain full access to the affected device's operating system. This vulnerability affects only Cisco ASR 1000 Series Routers that have removable line cards and Cisco cBR-8 Converged Broadband Routers, if they are running certain Cisco IOS XE 3.16 through 16.5 releases. Cisco Bug IDs: CSCvc65866, CSCve77132.

A vulnerability in the UDP processing code of Cisco IOS 15.1, 15.2, and 15.4 and IOS XE 3.14 through 3.18 could allow an unauthenticated, remote attacker to cause the input queue of an affected system to hold UDP packets, causing an interface queue wedge and a denial of service (DoS) condition. The vulnerability is due to Cisco IOS Software application changes that create UDP sockets and leave the sockets idle without closing them. An attacker could exploit this vulnerability by sending UDP packets with a destination port of 0 to an affected device. A successful exploit could allow the attacker to cause UDP packets to be held in the input interfaces queue, resulting in a DoS condition. The input interface queue will stop holding UDP packets when it receives 250 packets. Cisco Bug IDs: CSCup10024, CSCva55744, CSCva95506.

The Simple Network Management Protocol (SNMP) subsystem of Cisco IOS 12.0 through 12.4 and 15.0 through 15.6 and IOS XE 2.2 through 3.17 contains multiple vulnerabilities that could allow an authenticated, remote attacker to remotely execute code on an affected system or cause an affected system to reload. An attacker could exploit these vulnerabilities by sending a crafted SNMP packet to an affected system via IPv4 or IPv6. Only traffic directed to an affected system can be used to exploit these vulnerabilities. The vulnerabilities are due to a buffer overflow condition in the SNMP subsystem of the affected software. The vulnerabilities affect all versions of SNMP: Versions 1, 2c, and 3. To exploit these vulnerabilities via SNMP Version 2c or earlier, the attacker must know the SNMP read-only community string for the affected system. To exploit these vulnerabilities via SNMP Version 3, the attacker must have user credentials for the affected system. All devices that have enabled SNMP…

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE 3.16 could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to a race condition that could occur when the affected software processes an SNMP read request that contains certain criteria for a specific object ID (OID) and an active crypto session is disconnected on an affected device. An attacker who can authenticate to an affected device could trigger this vulnerability by issuing an SNMP request for a specific OID on the device. A successful exploit will cause the device to restart due to an attempt to access an invalid memory region. The attacker does not control how or when crypto sessions are disconnected on the device. Cisco Bug IDs: CSCvb94392.

A vulnerability in a startup script of Cisco IOS XE Software could allow an unauthenticated attacker with physical access to the targeted system to execute arbitrary commands on the underlying operating system with the privileges of the root user. More Information: CSCuz06639 CSCuz42122. Known Affected Releases: 15.6(1.1)S 16.1.2 16.2.0 15.2(1)E. Known Fixed Releases: Denali-16.1.3 16.2(1.8) 16.1(2.61) 15.6(2)SP 15.6(2)S1 15.6(1)S2 15.5(3)S3a 15.5(3)S3 15.5(2)S4 15.5(1)S4 15.4(3)S6a 15.4(3)S6 15.3(3)S8a 15.3(3)S8 15.2(5)E 15.2(4)E3 15.2(3)E5 15.0(2)SQD3 15.0(1.9.2)SQD3 3.9(0)E.