A vulnerability in the image verification feature of Cisco IOS Software for Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) could allow an authenticated, local attacker to boot a malicious software image on an affected device. The vulnerability is due to insufficient access restrictions on the area of code that manages the image verification feature. An attacker could exploit this vulnerability by first authenticating to the targeted device and then logging in to the Virtual Device Server (VDS) of an affected device. The attacker could then, from the VDS shell, disable Cisco IOS Software integrity (image) verification. A successful exploit could allow the attacker to boot a malicious Cisco IOS Software image on the targeted device. To exploit this vulnerability, the attacker must have valid user credentials at privilege level 15.

A vulnerability in the implementation of the inter-VM channel of Cisco IOS Software for Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an unauthenticated, adjacent attacker to execute arbitrary shell commands on the Virtual Device Server (VDS) of an affected device. The vulnerability is due to insufficient validation of signaling packets that are destined to VDS. An attacker could exploit this vulnerability by sending malicious packets to an affected device. A successful exploit could allow the attacker to execute arbitrary commands in the context of the Linux shell of VDS with the privileges of the root user. Because the device is designed on a hypervisor architecture, exploitation of a vulnerability that affects the inter-VM channel may lead to a complete system compromise. For more information about this vulnerability, see the Details section of this advisory.

A vulnerability in the Tool Command Language (Tcl) interpreter of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker with privileged EXEC credentials to execute arbitrary code on the underlying operating system (OS) with root privileges. The vulnerability is due to insufficient input validation of data passed to the Tcl interpreter. An attacker could exploit this vulnerability by loading malicious Tcl code on an affected device. A successful exploit could allow the attacker to cause memory corruption or execute the code with root privileges on the underlying OS of the affected device.

A vulnerability in the Tool Command Language (Tcl) interpreter of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker with privileged EXEC credentials to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient input validation of data passed to the Tcl interpreter. An attacker could exploit this vulnerability by executing crafted Tcl arguments on an affected device. An exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in the Secure Shell (SSH) server code of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. The vulnerability is due to an internal state not being represented correctly in the SSH state machine, which leads to an unexpected behavior. An attacker could exploit this vulnerability by creating an SSH connection to an affected device and using a specific traffic pattern that causes an error condition within that connection. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

Multiple vulnerabilities in the Cisco IOx application environment of Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) that are running Cisco IOS Software could allow an attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Multiple vulnerabilities in Cisco IOS Software for Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an unauthenticated, remote attacker or an authenticated, local attacker to execute arbitrary code on an affected system or cause an affected system to crash and reload. For more information about these vulnerabilities, see the Details section of this advisory.

A vulnerability in the FTP application layer gateway (ALG) functionality used by Network Address Translation (NAT), NAT IPv6 to IPv4 (NAT64), and the Zone-Based Policy Firewall (ZBFW) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a buffer overflow that occurs when an affected device inspects certain FTP traffic. An attacker could exploit this vulnerability by performing a specific FTP transfer through the device. A successful exploit could allow the attacker to cause the device to reload.

A vulnerability in the logic that handles access control to one of the hardware components in Cisco's proprietary Secure Boot implementation could allow an authenticated, local attacker to write a modified firmware image to the component. This vulnerability affects multiple Cisco products that support hardware-based Secure Boot functionality. The vulnerability is due to an improper check on the area of code that manages on-premise updates to a Field Programmable Gate Array (FPGA) part of the Secure Boot hardware implementation. An attacker with elevated privileges and access to the underlying operating system that is running on the affected device could exploit this vulnerability by writing a modified firmware image to the FPGA. A successful exploit could either cause the device to become unusable (and require a hardware replacement) or allow tampering with the Secure Boot verification process, which under some circumstances may allow the attacker to install and boot a malicious software image. An attacker will need to fulfill all the following conditions to attempt to exploit this vulnerability: Have privileged administrative access to the device. Be able to access the underlying operating system running on the device; this can be achieved either by using a supported, documented mechanism or by exploiting another vulnerability that would provide an attacker with such access. Develop or have access to a platform-specific exploit. An attacker attempting to exploit this vulnerability across multiple affected platforms would need to research each one of those platforms and then develop a platform-specific exploit. Although the research process could be reused across different platforms, an exploit developed for a given hardware platform is unlikely to work on a different hardware platform.

A vulnerability in the Secure Storage feature of Cisco IOS and IOS XE Software could allow an authenticated, local attacker to access sensitive system information on an affected device. The vulnerability is due to improper memory operations performed at encryption time, when affected software handles configuration updates. An attacker could exploit this vulnerability by retrieving the contents of specific memory locations of an affected device. A successful exploit could result in the disclosure of keying materials that are part of the device configuration, which can be used to recover critical system information.

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 Cisco Smart Call Home feature of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to gain unauthorized read access to sensitive data 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.

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 Network Address Translation 64 (NAT64) functions of Cisco IOS Software could allow an unauthenticated, remote attacker to cause either an interface queue wedge or a device reload. The vulnerability is due to the incorrect handling of certain IPv4 packet streams that are sent through the device. An attacker could exploit this vulnerability by sending specific IPv4 packet streams through the device. An exploit could allow the attacker to either cause an interface queue wedge or a device reload, resulting in a denial of service (DoS) condition.

A vulnerability in the Cisco Network Plug-and-Play (PnP) agent of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data. The vulnerability exists because the affected software insufficiently validates certificates. 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 and modify confidential information on user connections to the affected software.

A vulnerability in the processing of IP Service Level Agreement (SLA) packets by Cisco IOS Software and Cisco IOS XE software could allow an unauthenticated, remote attacker to cause an interface wedge and an eventual denial of service (DoS) condition on the affected device. The vulnerability is due to improper socket resources handling in the IP SLA responder application code. An attacker could exploit this vulnerability by sending crafted IP SLA packets to an affected device. An exploit could allow the attacker to cause an interface to become wedged, resulting in an eventual denial of service (DoS) condition on the affected device.

Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices that are running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later. Cisco Bug IDs: CSCuy32360, CSCuz60599.

Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices that are running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later. Cisco Bug IDs: CSCuy32360, CSCuz60599.

A vulnerability in the 802.1x multiple-authentication (multi-auth) feature of Cisco IOS Software could allow an unauthenticated, adjacent attacker to bypass the authentication phase on an 802.1x multi-auth port. The vulnerability is due to a logic change error introduced into the code. An attacker could exploit this vulnerability by trying to access an 802.1x multi-auth port after a successful supplicant has authenticated. An exploit could allow the attacker to bypass the 802.1x access controls and obtain access to the network. Cisco Bug IDs: CSCvg69701.

A vulnerability in conditional, verbose debug logging for the IPsec feature of Cisco IOS XE Software could allow an authenticated, local attacker to display sensitive IPsec information in the system log file. The vulnerability is due to incorrect implementation of IPsec conditional, verbose debug logging that causes sensitive information to be written to the log file. This information should be restricted. An attacker who has valid administrative credentials could exploit this vulnerability by authenticating to the device and enabling conditional, verbose debug logging for IPsec and viewing the log file. An exploit could allow the attacker to access sensitive information related to the IPsec configuration. Cisco Bug IDs: CSCvf12081.