OS Command Injection in Cisco IOS XR - CVE-2026-20040
Published: March 16, 2026
Vulnerability identifier: #VU124028
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20040
CWE-ID: CWE-78
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to execute arbitrary shell commands on the target system.
The vulnerability exists due to improper input validation in the CLI. A local user can pass specially crafted data to the application and execute arbitrary OS commands on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
Cisco IOS XR
How to mitigate CVE-2026-20040
Install updates from vendor's website.
Cisco IOS XR - addressed in versions 24.2.1, 24.2.2, 24.2.11, 24.2.20, 24.2.21, 24.3.1, 24.3.2, 24.3.20, 24.3.30, 24.4.1, 24.4.2, 24.4.10, 24.4.15, 24.4.30, 25.1.1, 25.1.2, 25.1.30, 25.2.1, 25.2.2, 25.2.15, 25.2.30, 25.3.1, 25.4.1, 26.1.1