Out-of-bounds write in Linux kernel - CVE-2026-64074
Published: July 20, 2026
Vulnerability identifier: #VU138555
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-64074
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an out-of-bounds write in statmount_mnt_idmap when handling mount ID mapping data in a seq_file buffer. A local user can trigger an integer count state that bypasses overflow detection to cause a denial of service.
The issue results in a 1-byte NULL out-of-bounds write on a dynamically allocated seq buffer.
How to mitigate CVE-2026-64074
Install security update from vendor's repository.