CVE-2025-39846 pcmcia: Fix a NULL pointer dereference in __iodyn_find_io_region()
A NULL pointer dereference in the Linux kernel PCMCIA subsystem can cause a system crash, requiring a kernel patch to fix.
- 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-2025-39846?
CVE-2025-39846 is a medium-severity vulnerability in Debian Debian Linux, published on 19 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:
pcmcia: Fix a NULL pointer dereference in __iodyn_find_io_region()
In __iodyn_find_io_region(), pcmcia_make_resource() is assigned to res and used in pci_bus_alloc_resource(). There is a dereference of res in pci_bus_alloc_resource(), which could lead to a NULL pointer dereference on failure of pcmcia_make_resource().
Fix this bug by adding a check of res.
Weakness: CWE-476
Which versions are affected by CVE-2025-39846?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2025-39846?
Apply the vendor's patch.
Is CVE-2025-39846 being exploited?
There is no known exploitation of CVE-2025-39846 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as AZL-67592, BELL-CVE-2025-39846, DEBIAN-CVE-2025-39846, GHSA-7jhx-j65p-qc96, ROOT-OS-DEBIAN-11-CVE-2025-39846, ROOT-OS-DEBIAN-12-CVE-2025-39846 and 4 more.