Description
In the Linux kernel, the following vulnerability has been resolved:
exfat: fix improper check of dentry.stream.valid_size
We found an infinite loop bug in the exFAT file system that can lead to a Denial-of-Service (DoS) condition. When a dentry in an exFAT filesystem is malformed, the following system calls — SYS_openat, SYS_ftruncate, and SYS_pwrite64 — can cause the kernel to hang.
Root cause analysis shows that the size validation code in exfat_find() does not check whether dentry.stream.valid_size is negative. As a result, the system calls mentioned above can succeed and eventually trigger the DoS issue.
This patch adds a check for negative dentry.stream.valid_size to prevent this vulnerability.
Metrics
No CVSS score has been published yet.
Affected software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 11a347fb6cef62ce47e84b97c45f2b2497c7593b, < 6c627bcc1896ba62ec793d0c00da74f3c93ce3ad; >= 11a347fb6cef62ce47e84b97c45f2b2497c7593b, < 204b1b02ee018ba52ad2ece21fe3a8643d66a1b2; >= 11a347fb6cef62ce47e84b97c45f2b2497c7593b, < 82ebecdc74ff555daf70b811d854b1f32a296bea |
| Linux | Linux | 6.8 |
References
Timeline
- Published
- Dec 6, 2025
- Last modified
- Oct 15, 2026
- NVD status
- Deferred