CVE-2025-40287

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.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/204b1b02ee018ba52ad2ece21fe3a8643d66a1b2
https://git.kernel.org/stable/c/6c627bcc1896ba62ec793d0c00da74f3c93ce3ad
https://git.kernel.org/stable/c/82ebecdc74ff555daf70b811d854b1f32a296bea

Configurations

No configuration.

History

No history.

Information

Published : 2025-12-06 22:15

Updated : 2026-06-17 09:21

NVD link : CVE-2025-40287

Mitre link : CVE-2025-40287

CVE.ORG link : CVE-2025-40287

JSON object : View

Products Affected

No product.

CWE

No CWE.

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