CVE-2025-70099

What it is

A NULL pointer dereference in the ext4_dir_en_get_name_len function in include/ext4_dir.h of lwext4 1.0.0 allows attackers to cause a denial of service by supplying a specially crafted EXT4 filesystem image with malformed directory entries. During directory iteration, the code may fail to validate the directory entry pointer before accessing the name_len field, resulting in a segmentation fault. This affects versions based on (or equivalent to) the 2016-era codebase (1.0.0).

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-06-01 21:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-07-22 08:10 UTC Last updatedMost recent change to the record

Details

Published

2026-06-01 21:16 UTC

Last modified

2026-07-22 08:10 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-476 · NULL pointer dereference

Record status

Deferred

Attack profile CVSS 3.1 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High