High 7.8Published Apr 22, 2026

CVE-2026-31447ext4: reject mount if bigalloc with s_first_data_block != 0

Updated under an hour ago (Oct 27, 2026, 7:40 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: ext4: reject mount if bigalloc with s_first_data_block != 0 bigalloc with s_first_data_block != 0 is not supported, reject mounting it.

CVSS: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-20
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	281b59959707dfae03ce038cdf231bf4904e170c builds before 5ad6d994255e27a3254079dfb50ca861fc31f2d0; 281b59959707dfae03ce038cdf231bf4904e170c builds before 3a926957cc95899ef88529710836edadc03c71a1; 281b59959707dfae03ce038cdf231bf4904e170c builds before 7b58c110b4e1f028eb38eec9ed3555e9be81c8b0; from 281b59959707dfae03ce038cdf231bf4904e170c before b77de3fceafbb39f30e4ff5dc986f863d5456417; from 281b59959707dfae03ce038cdf231bf4904e170c before d787d3ae96648dc14a3b7ca8fde817177e82c1c7; from 281b59959707dfae03ce038cdf231bf4904e170c before ad1f6d608f33f59d21a3d025615d6786a6443998; 281b59959707dfae03ce038cdf231bf4904e170c builds before 7d5b04290156c3fc316eecc86a4f9d201ab7d44a; from 281b59959707dfae03ce038cdf231bf4904e170c before 3822743dc20386d9897e999dbb990befa3a5b3f8	CNA record
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.6	CISA ADP
linux linux_kernel linux:linux_kernel	from 3.2 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.168; from 6.2 before 6.6.131; from 6.7 before 6.12.80; from 6.13 before 6.18.21; from 6.19 before 6.19.11; 7.0; and 4 more ranges	NVD

References

References

https://git.kernel.org/stable/c/5ad6d994255e27a3254079dfb50ca861fc31f2d0	patch
https://git.kernel.org/stable/c/3a926957cc95899ef88529710836edadc03c71a1	patch
https://git.kernel.org/stable/c/7b58c110b4e1f028eb38eec9ed3555e9be81c8b0	patch
https://git.kernel.org/stable/c/b77de3fceafbb39f30e4ff5dc986f863d5456417	patch
https://git.kernel.org/stable/c/d787d3ae96648dc14a3b7ca8fde817177e82c1c7	patch
https://git.kernel.org/stable/c/ad1f6d608f33f59d21a3d025615d6786a6443998	patch
https://git.kernel.org/stable/c/7d5b04290156c3fc316eecc86a4f9d201ab7d44a	patch
https://git.kernel.org/stable/c/3822743dc20386d9897e999dbb990befa3a5b3f8	patch
https://cert-portal.siemens.com/productcert/html/ssa-019113.html
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
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The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.