Information Disclosure in Linux Kernel Affecting Multiple Networking Components

CVE-2026-52937

What is CVE-2026-52937?

A vulnerability in the Linux kernel allows information disclosure through an uninitialized stack data leak in the SIOCGIFHWADDR path. The function tap_ioctl() copies an on-stack struct sockaddr_storage to user space, but due to improper initialization, users can access uninitialized trailing bytes. This flaw can expose sensitive kernel stack contents, undermining Kernel Address Space Layout Randomization (KASLR) defenses. The vulnerability has been addressed by initializing the stack struct at declaration to prevent any inadvertent exposure of critical information.

References