CVE-2026-31447
Mount Rejection Vulnerability in Linux ext4 bigalloc Feature
Publication date: 2026-04-22
Last updated on: 2026-04-27
Assigner: kernel.org
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux_kernel | linux_kernel | * |
| linux | linux_kernel | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability relates to the Linux kernel's ext4 filesystem. Specifically, it involves the bigalloc feature combined with a non-zero s_first_data_block value. The issue is that bigalloc with s_first_data_block set to a value other than zero is not supported, which could lead to problems when mounting the filesystem. The vulnerability has been resolved by rejecting the mount operation if these conditions are detected.
How can this vulnerability impact me? :
If a filesystem using bigalloc with s_first_data_block not equal to zero is mounted, it could cause mounting failures or unexpected behavior in the Linux kernel. This could lead to system instability or data access issues, potentially impacting system reliability and availability.