CVE-2025-70100 Denial of service in n/a
Attackers can cause a denial of service in the lwext4 library by providing a malformed ext4 filesystem image that triggers a divide-by-zero error.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-70100?
CVE-2025-70100 is a medium-severity denial of service vulnerability in n/a, published on 3 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-369
Which versions are affected by CVE-2025-70100?
It affects 1 product.
Products include Gkostka Lwext4.
How do I fix CVE-2025-70100?
No fix has been published for CVE-2025-70100 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-70100 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-70100 exists.
Other vulnerabilities in n/a
Sources
Also known as GHSA-43cg-f93f-9jhx.