CVE Watch22 jul 2026

CVE-2025-70100

A divide-by-zero vulnerability in the ext4_block_set_lb_size function in src/ext4_blockdev.c of the lwext4 1.0.0 library allows attackers to

CVSS

5.5

Medio

EPSS

0.2%

KEV

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Exploit Today

0-100

Publicado: 3 jun 2026 · Última mod.: 22 jul 2026 · CWE-369

EPSS · 30d

0.2%EPSS · 30 días0.2%

2026-07-042026-07-31

Descripción técnica

A divide-by-zero vulnerability in the ext4_block_set_lb_size function in src/ext4_blockdev.c of the lwext4 1.0.0 library allows attackers to cause a denial of service by providing a malformed ext4 filesystem image that results in a zero logical block size. The vulnerability is triggered during mount or image processing and leads to a Floating-Point Exception (FPE) under sanitizers or a runtime crash in standard builds due to missing validation of lb_size.

Referencias oficiales

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