Kernel Vulnerability in Linux Network Stack Affects HSR Frame Handling

CVE-2025-39703

What is CVE-2025-39703?

A vulnerability in the Linux kernel's network stack allows for malformed HSR frames to lead to system crashes. When the kernel receives a corrupt HSR frame with insufficient space in the socket buffer (skb) for the necessary headers, it triggers a panic during the skb_push operation. This situation arises from the HSR layer improperly queuing these corrupted frames, resulting in a critical failure when the kernel attempts to handle them. The improper handling can potentially allow an attacker to cause a denial of service by exploiting this flaw through carefully crafted network packets.

References