Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-06-25T00:00:00 kernel: fuse: reject fuse_notify() pagecache ops on directories 7.0 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H CWE-266

In the Linux kernel, the following vulnerability has been resolved: fuse: reject fuse_notify() pagecache ops on directories The operations FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE allow the FUSE daemon to actively write/read pagecache contents. For directories with FOPEN_CACHE_DIR, the pagecache is used as kernel-internal cache storage, and userspace is not supposed to have direct access to this cache - in particular, fuse_parse_cache() will hit WARN_ON() if the cache contains bogus data. Reject FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE on anything other than regular files with -EINVAL.

A flaw was found in the Linux kernel's Filesystem in Userspace (FUSE) component. The `fuse_notify()` function, specifically the `FUSE_NOTIFY_STORE` and `FUSE_NOTIFY_RETRIEVE` operations, allows the FUSE daemon to write or read pagecache contents. When these operations are performed on directories configured with `FOPEN_CACHE_DIR`, userspace can improperly access and manipulate kernel-internal cache storage. This could lead to system instability or a denial of service if the cache contains invalid data, potentially triggering a kernel warning.

Red Hat Enterprise Linux 10 Affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Affected kernel Red Hat Enterprise Linux 8 Affected kernel-rt Red Hat Enterprise Linux 9 Affected kernel Red Hat Enterprise Linux 9 Affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53168 https://nvd.nist.gov/vuln/detail/CVE-2026-53168 https://lore.kernel.org/linux-cve-announce/2026062551-CVE-2026-53168-7097@gregkh/T