CVE-2025-70099
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk26th percentile - higher than 26% of all known CVEs
Summary
A NULL pointer dereference vulnerability exists in the ext4_dir_en_get_name_len function in include/ext4_dir.h of lwext4 1.0.0. Attackers can cause a denial of service by supplying a specially crafted EXT4 filesystem image with malformed directory entries, leading to a segmentation fault due to missing validation of the directory entry pointer before accessing the name_len field.
Risk Assessment
The risk is a remote denial of service (DoS) attack via a malicious EXT4 image, potentially disrupting embedded systems or applications using lwext4.
Recommendation
Update lwext4 to a patched version that validates the directory entry pointer before accessing the name_len field. If no update is available, implement manual pointer validation in the source code.
Original NVD description (English source)
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).