CVE-2025-39924 erofs: fix invalid algorithm for encoded extents
A flaw in the Linux kernel EROFS filesystem allows invalid algorithm checks for encoded extents, potentially leading to system instability or denial of service.
- 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
- Available
What is CVE-2025-39924?
CVE-2025-39924 is a high-severity vulnerability in Linux kernel, published on 1 Oct 2025. 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
In the Linux kernel, the following vulnerability has been resolved:
erofs: fix invalid algorithm for encoded extents
The current algorithm sanity checks do not properly apply to new encoded extents.
Unify the algorithm check with Z_EROFS_COMPRESSION(_RUNTIME)_MAX and ensure consistency with sbi->available_compr_algs.
Which versions are affected by CVE-2025-39924?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-39924?
Apply the vendor's patch.
Is CVE-2025-39924 being exploited?
There is no known exploitation of CVE-2025-39924 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-39924, DEBIAN-CVE-2025-39924, GHSA-rx4q-q596-qrmv, UBUNTU-CVE-2025-39924.