CVE-2025-70101
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk18th percentile - higher than 18% of all known CVEs
Summary
An out-of-bounds read vulnerability exists in the ext4_ext_binsearch_idx function in src/ext4_extent.c of the lwext4 1.0.0 library. It is caused by insufficient validation of extent header fields before performing a binary search, leading to invalid pointer calculations and out-of-bounds memory read during extent tree traversal.
Risk Assessment
An attacker can exploit this vulnerability by supplying a specially crafted ext4 filesystem image, potentially causing a denial of service (DoS) through application crash or hang in software using the lwext4 library.
Recommendation
Update the lwext4 library to a patched version that fixes this vulnerability. Until then, avoid mounting untrusted ext4 images in applications relying on lwext4.
Original NVD description (English source)
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.