Improper update of reference count in Linux kernel - CVE-2026-53026
Published: June 25, 2026
Vulnerability identifier: #VU135347
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-53026
CWE-ID: CWE-911
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to improper reference count management in nfsd4_add_rdaccess_to_wrdeleg when handling concurrent NFS file access state updates. A remote user can trigger concurrent access patterns to cause a denial of service.
The issue can leave nfsd_file objects unreleased and trigger a BUG in kmem_cache_destroy() when the nfs-server service is stopped.
How to mitigate CVE-2026-53026
Install security update from vendor's repository.