{"id":"CVE-2026-31447","title":"ext4: reject mount if bigalloc with s_first_data_block != 0","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: reject mount if bigalloc with s_first_data_block != 0\n\nbigalloc with s_first_data_block != 0 is not supported, reject mounting\nit.","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 5ad6d994255e27a3254079dfb50ca861fc31f2d0","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 3a926957cc95899ef88529710836edadc03c71a1","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 7b58c110b4e1f028eb38eec9ed3555e9be81c8b0","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < b77de3fceafbb39f30e4ff5dc986f863d5456417","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < d787d3ae96648dc14a3b7ca8fde817177e82c1c7","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < ad1f6d608f33f59d21a3d025615d6786a6443998","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 7d5b04290156c3fc316eecc86a4f9d201ab7d44a","Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 3822743dc20386d9897e999dbb990befa3a5b3f8","Linux 3.2"],"published":"2026-04-22","updated":"2026-09-08","sourceUpdated":"2026-09-08T08:47:11.487Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-31447","references":[{"url":"https://git.kernel.org/stable/c/5ad6d994255e27a3254079dfb50ca861fc31f2d0"},{"url":"https://git.kernel.org/stable/c/3a926957cc95899ef88529710836edadc03c71a1"},{"url":"https://git.kernel.org/stable/c/7b58c110b4e1f028eb38eec9ed3555e9be81c8b0"},{"url":"https://git.kernel.org/stable/c/b77de3fceafbb39f30e4ff5dc986f863d5456417"},{"url":"https://git.kernel.org/stable/c/d787d3ae96648dc14a3b7ca8fde817177e82c1c7"},{"url":"https://git.kernel.org/stable/c/ad1f6d608f33f59d21a3d025615d6786a6443998"},{"url":"https://git.kernel.org/stable/c/7d5b04290156c3fc316eecc86a4f9d201ab7d44a"},{"url":"https://git.kernel.org/stable/c/3822743dc20386d9897e999dbb990befa3a5b3f8"}],"tags":["cve.org"],"epss":0.00143,"epssPercentile":0.03936,"ingestedAt":"2026-09-08T15:33:26.990Z","slug":"CVE-2026-31447","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\next4: reject mount if bigalloc with s_first_data_block != 0\n\nbigalloc with s_first_data_block != 0 is not supported, reject mounting\nit.\n\n## Affected\n\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 5ad6d994255e27a3254079dfb50ca861fc31f2d0`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 3a926957cc95899ef88529710836edadc03c71a1`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 7b58c110b4e1f028eb38eec9ed3555e9be81c8b0`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < b77de3fceafbb39f30e4ff5dc986f863d5456417`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < d787d3ae96648dc14a3b7ca8fde817177e82c1c7`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < ad1f6d608f33f59d21a3d025615d6786a6443998`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 7d5b04290156c3fc316eecc86a4f9d201ab7d44a`\n- `Linux >= 281b59959707dfae03ce038cdf231bf4904e170c < 3822743dc20386d9897e999dbb990befa3a5b3f8`\n- `Linux 3.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}