CVE-2026-20040: Cisco IOS XR Software CLI Privilege Escalation Vulnerability
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-20040?
The severity of CVE-2026-20040 is classified as critical due to the potential for privilege escalation.
How do I fix CVE-2026-20040?
To fix CVE-2026-20040, you should upgrade to a patched version of Cisco IOS XR Software as recommended by Cisco.
Who is affected by CVE-2026-20040?
Authenticated local attackers on devices running vulnerable versions of Cisco IOS XR Software are affected by CVE-2026-20040.
What can an attacker do with CVE-2026-20040?
An attacker exploiting CVE-2026-20040 can execute arbitrary commands as root, compromising the underlying operating system.
Is there a workaround for CVE-2026-20040?
There are currently no recommended workarounds for CVE-2026-20040; upgrading to a secure version is essential.