CVE-2025-71115 um: init cpu_tasks[] earlier
A null pointer dereference in the Linux kernel UML subsystem causes a crash when KCOV is enabled during early initialization.
- 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-2025-71115?
CVE-2025-71115 is a medium-severity vulnerability in Linux kernel, published on 14 Jan 2026. 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:
um: init cpu_tasks[] earlier
This is currently done in uml_finishsetup(), but e.g. with KCOV enabled we'll crash because some init code can call into e.g. memparse(), which has coverage annotations, and then the checks in check_kcov_mode() crash because current is NULL.
Simply initialize the cpu_tasks[] array statically, which fixes the crash. For the later SMP work, it seems to have not really caused any problems yet, but initialize all of the entries anyway.
Weakness: CWE-908
Which versions are affected by CVE-2025-71115?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-71115?
Apply the vendor's patch.
Is CVE-2025-71115 being exploited?
There is no known exploitation of CVE-2025-71115 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-71115, DEBIAN-CVE-2025-71115, GHSA-743m-w227-wrrf, ROOT-OS-UBUNTU-2204-CVE-2025-71115, ROOT-OS-UBUNTU-2404-CVE-2025-71115, UBUNTU-CVE-2025-71115.