A vulnerability in task group assignment for a specific CLI command in Cisco IOS XR Software could allow an authenticated, local attacker to elevate privileges and gain full administrative control of an affected device.
This vulnerability is due to incorrect mapping of a command to task groups within the source code. An attacker with a low-privileged account could exploit this vulnerability by using the CLI command to bypass the task group–based checks. A successful exploit could allow the attacker to elevate privileges and perform actions on an affected device without authorization checks.
A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the IS-IS process to restart unexpectedly.
This vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending crafted IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process to restart unexpectedly, resulting in a temporary loss of connectivity to advertised networks and a denial of service (DoS) condition.
Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency.
A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary commands as root on the underlying operating system of an affected device.
This vulnerability is due to insufficient validation of user arguments that are passed to specific CLI commands. An attacker with a low-privileged account could exploit this vulnerability by using crafted commands at the prompt. A successful exploit could allow the attacker to elevate privileges to root and execute arbitrary commands on the underlying operating system.
A vulnerability in the boot process of Cisco IOS XR Software could allow an authenticated, local attacker to bypass Cisco IOS XR image signature verification and load unverified software on an affected device. To exploit this vulnerability, the attacker must have root-system privileges on the affected device.
This vulnerability is due to incomplete validation of files in the boot verification process. An attacker could exploit this vulnerability by manipulating the system configuration options to bypass some of the integrity checks that are performed during the boot process. A successful exploit could allow the attacker to control the boot configuration, which could enable them to bypass the requirement to run Cisco-signed images or alter the security properties of the running system.
Note: Because exploitation of this vulnerability could result in the attacker bypassing Cisco image verification, Cisco has raised the Security Impact Rating (SIR) of this advisory from Medium to High.
A vulnerability in the GRand Unified Bootloader (GRUB) for Cisco IOS XR Software could allow an unauthenticated attacker with physical access to the device to view sensitive files on the console using the GRUB bootloader command line. This vulnerability is due to the inclusion of unnecessary commands within the GRUB environment that allow sensitive files to be viewed. An attacker could exploit this vulnerability by being connected to the console port of the Cisco IOS XR device when the device is power-cycled. A successful exploit could allow the attacker to view sensitive files that could be used to conduct additional attacks against the device.
A vulnerability in the Topology Discovery Service of Cisco One Platform Kit (onePK) in Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient length restrictions when the onePK Topology Discovery Service parses Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol message to an affected device. An exploit could allow the attacker to cause a stack overflow, which could allow the attacker to execute arbitrary code with administrative privileges, or to cause a process crash, which could result in a reload of the device and cause a DoS condition.
The SNMPv2 implementation in Cisco IOS XR allows remote authenticated users to cause a denial of service (snmpd daemon reload) via a malformed SNMP packet, aka Bug ID CSCur25858.