SB2026090436 - Use-after-free in Linux kernel kvm mmu
Published: September 4, 2026
Security Bulletin ID
SB2026090436
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) Use-after-free (CVE-ID: CVE-2026-80726)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause memory corruption.
The vulnerability exists due to a use-after-free in the KVM x86 MMU when creating a child shadow page from an invalid parent shadow page. A local user can trigger KVM to create such a child shadow page to cause memory corruption.
The condition involves an invalid shadow page being present on the list of active MMU pages.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/0af4711862c5b818204d40b21f0859ad51c230e9
- https://git.kernel.org/stable/c/5ec42d57655c690234c14aece6dd3f209778c1d8
- https://git.kernel.org/stable/c/66bc868a33cf1de43f22a94acd8857e0fe33393f
- https://git.kernel.org/stable/c/9b7984692c18b22d6d61af3f53887fca7fddb0f1
- https://git.kernel.org/stable/c/9f7760a2e962cbda0d096a27d394d14ad4d22928
- https://git.kernel.org/stable/c/f33ecb89d352348ed5e625f6747ac51ede254e1b