cvedb.io
CVE-2025-40307
HIGH · CVSS 7.8
EPSS exploitation probability: 0%
Published 2025-12-08T01:16:02.950 · Last modified 2026-07-30T06:24:28.180

Summary

In the Linux kernel, the following vulnerability has been resolved: exfat: validate cluster allocation bits of the allocation bitmap syzbot created an exfat image with cluster bits not set for the allocation bitmap. exfat-fs reads and uses the allocation bitmap without checking this. The problem is that if the start cluster of the allocation bitmap is 6, cluster 6 can be allocated when creating a directory with mkdir. exfat zeros out this cluster in exfat_mkdir, which can delete existing entries. This can reallocate the allocated entries. In addition, the allocation bitmap is also zeroed out, so cluster 6 can be reallocated. This patch adds exfat_test_bitmap_range to validate that clusters used for the allocation bitmap are correctly marked as in-use.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.