EUVD-2026-39259
GHSA-r29v-cgxr-pghg
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Local-only vector requires FUSE daemon control with low privileges; pure DoS via kernel crash with no confirmed confidentiality or integrity impact per vendor scoring.
Primary rating from NVD.
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
5DescriptionNVD
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.
AnalysisAI
Kernel crash via FUSE pagecache misuse in the Linux kernel allows a local low-privileged user controlling a FUSE daemon to trigger a WARN_ON() assertion in fuse_parse_cache() by sending FUSE_NOTIFY_STORE or FUSE_NOTIFY_RETRIEVE notifications targeting directory inodes instead of regular files, causing a denial-of-service kernel crash. The vulnerability specifically affects FUSE filesystems that have directory caching (FOPEN_CACHE_DIR) enabled, a non-default configuration that exposes kernel-internal pagecache storage to invalid manipulation. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires local system access and the ability to control a FUSE daemon - either by launching one directly via unprivileged user namespaces (available by default on many desktop Linux distributions and some cloud images, but disabled on hardened enterprise distributions) or by compromising an existing FUSE daemon process. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 3.1 score of 5.5 Medium with vector AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H accurately characterizes real-world risk. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | A local user with unprivileged user namespace access runs a custom FUSE daemon and mounts a FUSE filesystem with directory caching (FOPEN_CACHE_DIR) enabled. The user then sends FUSE_NOTIFY_STORE or FUSE_NOTIFY_RETRIEVE pagecache notifications directed at a cached directory inode rather than a regular file; fuse_parse_cache() processes the resulting malformed pagecache state, fires WARN_ON(), and crashes the kernel. … |
| Remediation | The primary remediation is upgrading to a patched kernel version: 5.10.259+ for the 5.10 LTS branch, 5.15.210+ for 5.15 LTS, 6.1.176+ for 6.1 LTS, 6.6.143+ for 6.6, 6.12.94+ for 6.12, 7.0.13+ for 7.0, or 7.1 final. … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
Same technique Information Disclosure
View allShare
External POC / Exploit Code
Leaving vuln.today