CVE-2025-70100: n/a
A divide-by-zero vulnerability in the ext4_block_set_lb_size function in src/ext4_blockdev.c of the lwext4 1.0.0 library allows attackers to cause a denial of service by providing a malformed ext4 filesystem image that results in a zero logical block size. The vulnerability is triggered during mount or image processing and leads to a Floating-Point Exception (FPE) under sanitizers or a runtime crash in standard builds due to missing validation of lb_size.
AI Analysis
Technical Summary
This vulnerability in lwext4 version 1.0.0 arises from a lack of validation for the logical block size (lb_size) in the ext4_block_set_lb_size function within src/ext4_blockdev.c. When an attacker provides a malformed ext4 filesystem image that sets lb_size to zero, the function performs a divide-by-zero operation. This leads to a denial of service by causing a runtime crash or a floating-point exception under sanitizers during mounting or image processing.
Potential Impact
Successful exploitation causes a denial of service by crashing the application processing the ext4 filesystem image. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid mounting or processing untrusted ext4 filesystem images with this library version.
CVE-2025-70100: n/a
Description
A divide-by-zero vulnerability in the ext4_block_set_lb_size function in src/ext4_blockdev.c of the lwext4 1.0.0 library allows attackers to cause a denial of service by providing a malformed ext4 filesystem image that results in a zero logical block size. The vulnerability is triggered during mount or image processing and leads to a Floating-Point Exception (FPE) under sanitizers or a runtime crash in standard builds due to missing validation of lb_size.
CVSS v3.1
Score 5.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in lwext4 version 1.0.0 arises from a lack of validation for the logical block size (lb_size) in the ext4_block_set_lb_size function within src/ext4_blockdev.c. When an attacker provides a malformed ext4 filesystem image that sets lb_size to zero, the function performs a divide-by-zero operation. This leads to a denial of service by causing a runtime crash or a floating-point exception under sanitizers during mounting or image processing.
Potential Impact
Successful exploitation causes a denial of service by crashing the application processing the ext4 filesystem image. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid mounting or processing untrusted ext4 filesystem images with this library version.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-01-09T00:00:00.000Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a2037c3e29bf47b50c14d98
Added to database: 06/03/2026, 14:18:43 UTC
Last enriched: 06/29/2026, 20:58:33 UTC
Last updated: 07/31/2026, 19:22:56 UTC
Views: 39
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