lwext4 1.0.0 include/ext4_dir.h ext4_dir_en_get_name_len null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability was found in lwext4 1.0.0 and classified as problematic. The impacted element is the function ext4_dir_en_get_name_len in the library include/ext4_dir.h. The manipulation of the argument name_len results in null pointer dereference. This vulnerability is known as CVE-2025-70099. Furthermore, an exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in lwext4 1.0.0. Affected is the function ext4_dir_en_get_name_len in the library include/ext4_dir.h. The manipulation of the argument name_len with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

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).

The advisory is available at github.com. This vulnerability is traded as CVE-2025-70099 since 01/09/2026. Technical details and a public exploit are known.

The exploit is shared for download at github.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 3.5
VulDB Temp Score: 3.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 7.5
ADP CISA Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/09/2026 CVE reserved
06/02/2026 +143 days Advisory disclosed
06/02/2026 +0 days VulDB entry created
06/29/2026 +27 days VulDB entry last update

Sourcesinfo

Advisory: 89
Status: Confirmed

CVE: CVE-2025-70099 (🔒)
GCVE (CVE): GCVE-0-2025-70099
GCVE (VulDB): GCVE-100-367770
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 06/02/2026 07:55
Updated: 06/29/2026 23:57
Changes: 06/02/2026 07:55 (58), 06/29/2026 23:57 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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