CVE-2025-70101

medium

Description

An out-of-bounds read in the ext4_ext_binsearch_idx function in src/ext4_extent.c of the lwext4 1.0.0 library allows attackers to cause a denial of service by supplying a specially crafted ext4 filesystem image. The vulnerability occurs due to insufficient validation of extent header fields before performing a binary search over extent index entries, which can result in invalid pointer calculations and an out-of-bounds memory read during extent tree traversal.

References

https://infosec.exchange/@sigdevel/116668958927817708

https://github.com/sigdevel/pocs/blob/main/res/lwext4/3/sig11_lwext4_ext4_extent_815

https://github.com/gkostka/lwext4/issues/91

http://www.openwall.com/lists/oss-security/2026/06/29/6

Details

Source: Mitre, NVD

Published: 2026-06-03

Updated: 2026-06-29

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N

Severity: High

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.00027