Use-after-free in Linux kernel - CVE-2026-63816
Published: July 21, 2026
Vulnerability identifier: #VU138840
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-2026-63816
CWE-ID: CWE-416
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 a use-after-free in the f2fs garbage collection code when handling F2FS_IOC_GARBAGE_COLLECT_RANGE on a copy-on-write file. A local user can trigger garbage collection while the associated atomic inode is being evicted to cause a denial of service.
The issue involves access to atomic_inode->i_mapping without holding a reference to the atomic inode.
How to mitigate CVE-2026-63816
Install security update from vendor's repository.