CVE-2025-39743 jfs: truncate good inode pages when hard link is 0
A bug in the Linux kernel JFS filesystem causes a kernel panic when evicting an inode with zero hard links, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-39743?
CVE-2025-39743 is a high-severity vulnerability in Debian Debian Linux, published on 11 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
jfs: truncate good inode pages when hard link is 0
The fileset value of the inode copy from the disk by the reproducer is AGGR_RESERVED_I. When executing evict, its hard link number is 0, so its inode pages are not truncated. This causes the bugon to be triggered when executing clear_inode() because nrpages is greater than 0.
Which versions are affected by CVE-2025-39743?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2025-39743?
Apply the vendor's patch.
Is CVE-2025-39743 being exploited?
There is no known exploitation of CVE-2025-39743 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as BELL-CVE-2025-39743, DEBIAN-CVE-2025-39743, GHSA-q96w-jvgq-x3hx, ROOT-OS-DEBIAN-11-CVE-2025-39743, ROOT-OS-DEBIAN-12-CVE-2025-39743, ROOT-OS-UBUNTU-2204-CVE-2025-39743 and 2 more.