CVE-2025-39968 i40e: add max boundary check for VF filters
A missing boundary check in the i40e network driver allows a virtual function to request excessive filters, potentially causing a 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-2025-39968?
CVE-2025-39968 is a high-severity denial of service vulnerability in Linux, published on 15 Oct 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:
i40e: add max boundary check for VF filters
There is no check for max filters that VF can request. Add it.
Which versions are affected by CVE-2025-39968?
How do I fix CVE-2025-39968?
Apply the vendor's patch.
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-2025-39968 being exploited?
There is no known exploitation of CVE-2025-39968 in the wild and no public exploit code.
Sources
Also known as AZL-68465, BELL-CVE-2025-39968, DEBIAN-CVE-2025-39968, GHSA-prj5-rqwf-24v6, ROOT-OS-DEBIAN-11-CVE-2025-39968, ROOT-OS-DEBIAN-12-CVE-2025-39968 and 3 more.