Out-of-bounds write in Linux kernel - CVE-2026-89754
Published: September 12, 2026
Vulnerability identifier: #VU149049
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89754
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause an out-of-bounds write.
The vulnerability exists due to improper state management in the Linux kernel mm/pagewalk page-table walker when walking page tables after a PMD entry is cleared during a retry. A local user can trigger duplicate page-walk callbacks through the mincore system call to cause an out-of-bounds write.
Affected software
Linux kernel
How to mitigate CVE-2026-89754
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3