CVE-2025-39781 parisc: Drop WARN_ON_ONCE() from flush_cache_vmap
A warning trigger in the Linux kernel's parisc architecture can lead to system instability or 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-2025-39781?
CVE-2025-39781 is a medium-severity denial of service vulnerability in Linux kernel, 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:
parisc: Drop WARN_ON_ONCE() from flush_cache_vmap
I have observed warning to occassionally trigger.
Which versions are affected by CVE-2025-39781?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-39781?
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-2025-39781 being exploited?
There is no known exploitation of CVE-2025-39781 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-67151, BELL-CVE-2025-39781, DEBIAN-CVE-2025-39781, GHSA-35wp-vg6r-qrm4, ROOT-OS-DEBIAN-11-CVE-2025-39781, ROOT-OS-DEBIAN-12-CVE-2025-39781 and 4 more.