CVE-2025-39810 bnxt_en: Fix memory corruption when FW resources change during ifdown
A memory corruption vulnerability in the Linux kernel bnxt_en driver allows attackers to cause denial of service or execute code when firmware resources change during interface shutdown.
- 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-2025-39810?
CVE-2025-39810 is a high-severity memory corruption vulnerability in Linux kernel, published on 16 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:
bnxt_en: Fix memory corruption when FW resources change during ifdown
bnxt_set_dflt_rings() assumes that it is always called before any TC has been created. So it doesn't take bp->num_tc into account and assumes that it is always 0 or 1.
In the FW resource or capability change scenario, the FW will return flags in bnxt_hwrm_if_change() that will cause the driver to reinitialize and call bnxt_cancel_reservations(). This will lead to bnxt_init_dflt_ring_mode() calling bnxt_set_dflt_rings() and bp->num_tc may be greater than 1. This will cause bp->tx_ring[] to be sized too small and cause memory corruption in bnxt_alloc_cp_rings().
Fix it by properly scaling the TX rings by bp->num_tc in the code paths mentioned above. Add 2 helper functions to determine bp->tx_nr_rings and bp->tx_nr_rings_per_tc.
Weakness: CWE-787
Which versions are affected by CVE-2025-39810?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-39810?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-39810 being exploited?
There is no known exploitation of CVE-2025-39810 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-67431, AZL-71206, BELL-CVE-2025-39810, DEBIAN-CVE-2025-39810, GHSA-rv8g-6vr7-cv64, ROOT-OS-DEBIAN-11-CVE-2025-39810 and 5 more.