PT-2026-45934 · Lwext4 · Lwext4

CVE-2025-70100 · Published 2026-06-03 · Updated 2026-07-01

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions lwext4 version 1.0.0

Description A divide-by-zero issue exists in the ext4 block set lb size() function within the src/ext4 blockdev.c file. This occurs when a malformed ext4 filesystem image with a zero logical block size is provided, leading to a denial of service. The issue is triggered during image processing or mounting and results in a runtime crash or a Floating-Point Exception (FPE), which is an error occurring when a program attempts an illegal arithmetic operation. The root cause is the missing validation of the lb size variable.

Recommendations For version 1.0.0, at the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

DoS

Divide By Zero

Weakness Enumeration

CWE-369

Related Identifiers

CVE-2025-70100

Affected Products

Lwext4

References · 11

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/70xxx/CVE-2025-70100.json · Exploit
• 🔥 https://github.com/gkostka/lwext4/issues/90 · Exploit
• 🔥 https://github.com/sigdevel/pocs/blob/main/res/lwext4/2/sig8_2_lwext4_ext4_blockdev_c_127 · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2025-70100 · Security Note
• https://infosec.exchange/@sigdevel/116668952003072580 · Patch
• https://osv.dev/vulnerability/CVE-2025-70100 · Vendor Advisory
• http://openwall.com/lists/oss-security/2026/06/29/5 · Note
• https://twitter.com/oss_security/status/2072379584230682874 · Twitter Post
• https://t.me/cveNotify/179190 · Telegram Post
• https://t.me/cveNotify/166296 · Telegram Post
• https://t.me/CVEtracker/55714 · Telegram Post