Improper control of a resource through its lifetime in Linux kernel - CVE-2026-64063
Published: July 20, 2026
Vulnerability identifier: #VU138581
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-64063
CWE-ID: CWE-664
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 corrupt file data.
The vulnerability exists due to improper state management in netfs_perform_write() when handling streaming writes that overwrite partially written folios. A local user can perform crafted write operations to corrupt file data.
The issue can be triggered on netfs-backed filesystems such as cifs with the default cache option, and was observed when a streaming write page is later overwritten entirely or partially by a single write().
How to mitigate CVE-2026-64063
Install security update from vendor's repository.