CVE-2026-72037 net: lan743x: Initialize eth_syslock spinlock before use
A missing spinlock initialization in the lan743x driver can cause a kernel crash during device probe when debug options are enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72037?
CVE-2026-72037 is a vulnerability in Linux, published on 15 Aug 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:
net: lan743x: Initialize eth_syslock spinlock before use
lan743x_hardware_init() calls pci11x1x_strap_get_status() during the PCI11x1x probe sequence. That helper acquires the Ethernet subsystem hardware lock via lan743x_hs_syslock_acquire(), which relies on adapter->eth_syslock_spinlock to serialize access.
The spinlock is currently initialized only after the strap status is read. With CONFIG_DEBUG_SPINLOCK enabled, taking the zeroed initialized spinlock can trip the spinlock debug check.
Fix by initializing adapter->eth_syslock_spinlock before reading the strap status so the probe path never attempts to lock an uninitialized spinlock.
Which versions are affected by CVE-2026-72037?
How do I fix CVE-2026-72037?
Apply the vendor's patch.
Is CVE-2026-72037 being exploited?
There is no known exploitation of CVE-2026-72037 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72037, DEBIAN-CVE-2026-72037, GHSA-57rg-9qx8-7v7g, UBUNTU-CVE-2026-72037.