SB2026031632 - Multiple vulnerabilities in Cisco IOS XR Software
Published: March 16, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) OS Command Injection (CVE-ID: CVE-2026-20040)
CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CVSSv4: 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/E:U/U:Clear
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.
2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2026-20046)
CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to incorrect mapping of a command to task groups within the source code, which leads to security restrictions bypass and privilege escalation.
Remediation
Install update from vendor's website.