CVE-2026-53167
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk2th percentile — higher than 2% of all known CVEs
Summary
In the Linux kernel, a vulnerability was found in the FUSE filesystem where FUSE_NOTIFY_RETRIEVE requests could return data from non-uptodate folios containing uninitialized data. This affects systems without automatic zero-initialization of page allocations (CONFIG_INIT_ON_ALLOC_DEFAULT_ON or init_on_alloc=1).
Risk Assessment
The organization may face a risk of sensitive data leakage if an attacker exploits this vulnerability to read uninitialized kernel memory, potentially leading to information disclosure.
Recommendation
Immediately update the Linux kernel to a version containing the fix that limits FUSE_NOTIFY_RETRIEVE to uptodate folios. For systems without the patch, enable init_on_alloc=1 in kernel boot parameters.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: fuse: limit FUSE_NOTIFY_RETRIEVE to uptodate folios FUSE_NOTIFY_RETRIEVE must be limited to uptodate folios; !uptodate folios can contain uninitialized data. Since FUSE_NOTIFY_RETRIEVE is intended to only return data that is already in the page cache and not wait for data from the FUSE daemon, treat !uptodate folios as if they weren't present. This only has security impact on systems that don't enable automatic zero-initialization of all page allocations via CONFIG_INIT_ON_ALLOC_DEFAULT_ON or init_on_alloc=1.