SB2026090573 - Improper Initialization in Linux kernel arm64 kvm
Published: September 5, 2026
Security Bulletin ID
SB2026090573
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper Initialization (CVE-ID: CVE-2026-80873)
CWE-ID: CWE-665 - Improper Initialization
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a guest L2 hypervisor to observe a stale ESR_EL2 value.
The vulnerability exists due to improper initialization of ESR_EL2 in kvm_inject_el2_exception() when injecting nested SError exceptions. A local user can trigger a nested SError exception to cause a guest L2 hypervisor to observe a stale ESR_EL2 value.
The issue also affects the EASE path in kvm_inject_nested_sea().
Remediation
Install update from vendor's website.