Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: xsk: clear metadata pointer when no timestamp is requested User space can change… (CVE-2026-74709)

The Linux kernel vulnerability (CVE-2026-74709) involved the xsk (AF_XDP) subsystem where user space could modify metadata flags after the kernel had processed a request. This led to the kernel potentially writing a timestamp that was not requested when the packet was submitted. The fix clears the metadata pointer during request processing unless a timestamp completion is requested, allowing completion handling to use the pointer directly instead of rereading flags. On the mlx5 multi-packet WQE path, metadata is evaluated per batch, and only the descriptor starting a session resets the pointer, preventing unintended timestamp writes for other descriptors. Other zero-copy and generic paths reset the pointer per descriptor and remain unaffected.

User space could cause the kernel to write timestamps that were not requested, potentially leading to inaccurate metadata being recorded for packets. This could affect packet processing and timestamp reliability in the AF_XDP subsystem, but the write remains confined to the metadata area and does not indicate broader memory corruption or privilege escalation.

A fix has been implemented in the Linux kernel to clear the metadata pointer during request processing unless a timestamp completion is requested. Users should apply the official kernel updates that include this fix. Since this is a kernel-level vulnerability, updating to the patched kernel version is the recommended remediation. No additional mitigation steps are indicated.