CVE-2026-43050

A flaw was found in the Linux kernel's Asynchronous Transfer Mode (ATM) LAN Emulation Client (LEC) module. A race condition exists where the priv->lecd pointer can be set to NULL while other threads are still accessing it. This can lead to a use-after-free memory corruption vulnerability when the socket's wait queue is accessed, potentially causing system instability or a denial of service. The issue stems from insufficient synchronization during the clearing of the priv->lecd pointer.

LAN Emulation (LEC) ATM path could UAF in sock_def_readable() during async disconnect; upstream fixes reference lifetimes. Red Hat recommends patched kernels where lec is used; unload module if ATM LANE unused.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, prevent the lec module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.