The Linux kernel vulnerability CVE-2026-81002 involves the xdp_convert_zc_to_xdp_frame() function, which clones an AF_XDP zero-copy packet into an order-0 page and advertises PAGE_SIZE as the frame size. This allows the copied frame to occupy the page tail needed by skb_shared_info or to place it beyond the allocated page, resulting in overlapping or out-of-bounds memory access. This flaw can cause a slab-out-of-bounds write detected by KASAN and lead to kernel panics. The patch restricts the copied layout to SKB_WITH_OVERHEAD(PAGE_SIZE) and includes metadata length in the frame headroom to prevent these issues.

The vulnerability can cause out-of-bounds memory writes within the kernel memory allocator slab, potentially leading to kernel panics and system instability. This affects the AF_XDP zero-copy packet processing path and can disrupt normal network packet handling. There is no indication of remote code execution or privilege escalation from the provided data.

A fix has been implemented in the Linux kernel to address this vulnerability by limiting the copied frame layout size and properly accounting for metadata length. Users should apply the official kernel updates that include this patch. No additional mitigation steps are indicated or required beyond applying the fix.