Input validation error in Cisco IOS XE - CVE-2026-20273
Published: August 6, 2026
Vulnerability identifier: #VU141053
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20273
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to improper input validation in Cisco IOS XE Software when processing input. A remote attacker can send specially crafted input and perform a denial of service attack.
Affected software
Cisco IOS XE
How to mitigate CVE-2026-20273
Install security update from vendor's website.
Cisco IOS XE - addressed in versions 17.9.10, 17.12.8, 17.15.6, 17.18.4, 17.18.4a, 26.1.2