Infinite loop in Linux kernel - CVE-2026-89991
Published: September 16, 2026
Vulnerability identifier: #VU150292
CSH Severity: Low
CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89991
CWE-ID: CWE-835
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an infinite loop in __pcpu_freelist_push() when an NMI re-enters pcpu_freelist_push() while the interrupted context holds the only possible CPU's freelist lock. A local user can trigger the affected BPF freelist push path to cause a denial of service.
The issue occurs on systems with only one possible CPU.
Affected software
Linux kernel
How to mitigate CVE-2026-89991
Install security update from vendor's repository.