Insufficient Control Flow Management in Cisco IOS XR - CVE-2026-20276
Published: September 2, 2026
Vulnerability identifier: #VU146766
CSH Severity: High
CVSS v4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20276
CWE-ID: CWE-691
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to insufficient control flow management in Cisco IOS XR Software when processing network input. A remote attacker can send crafted input to cause a denial of service.
The covered issues include reachable assertion and loop with unreachable exit condition.
Affected software
Cisco IOS XR
How to mitigate CVE-2026-20276
Install security update from vendor's website.
Cisco IOS XR - addressed in versions 26.2.2, 26.3.1