Resource exhaustion in Linux kernel - CVE-2026-89604
Published: September 12, 2026
Vulnerability identifier: #VU149197
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89604
CWE-ID: CWE-400
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 uncontrolled resource consumption in the efivarfs statfs() handler when repeatedly invoking statfs() on the efivarfs mount point. A local user can flood the QueryVariableInfo() runtime service with statfs() calls to cause a denial of service.
On x86 systems with a variable store backed by SMM, each runtime-service entry requires a rendezvous of all CPUs.
Affected software
Linux kernel
How to mitigate CVE-2026-89604
Install security update from vendor's repository.