XDP Fragmentation Vulnerability in Linux Kernel Affects Mellanox Drivers

CVE-2026-43464

What is CVE-2026-43464?

In the Linux kernel, a vulnerability pertaining to erroneous handling of XDP buffer fragments has been identified within the Mellanox drivers. This vulnerability stems from incorrect assumptions regarding the XDP buffer layout during the execution of programs that modify this layout. The issue lies in the driver failing to properly count dropped fragments, leading to potential page reference counting anomalies. This can result in negative reference counts, as noted in specific selftests, ultimately leading to system warnings and stability risks. The fix reverts certain changes to regain proper fragment counting while ensuring compatibility with original XDP operations.

References