CVE-2026-81002 xdp: fix zero-copy frame layout
A memory corruption flaw in the Linux kernel's XDP zero-copy path allows attackers to cause out-of-bounds writes, leading to system crashes or potential code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-81002?
CVE-2026-81002 is a critical memory corruption vulnerability in Linux, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
xdp: fix zero-copy frame layout
xdp_convert_zc_to_xdp_frame() clones an XSK packet into an order-0 page and advertises PAGE_SIZE as its frame size. It allows the copied frame to occupy the page tail needed by skb_shared_info and records zero headroom even when metadata separates the frame header from packet data. An AF_XDP zero-copy packet redirected through cpumap can therefore make the skb overlap skb_shared_info or place it beyond the allocated page.
Limit the copied layout to SKB_WITH_OVERHEAD(PAGE_SIZE) and include the metadata length in frame headroom. Redirect callers already handle a NULL conversion result.
BUG: KASAN: slab-out-of-bounds in skb_gro_receive Write of size 4 at addr ffff88800cf37004 by task cpumap/1/map:1/146 Call Trace: skb_gro_receive (net/core/gro.c:174) udp_gro_receive (net/ipv4/udp_offload.c:812) inet_gro_receive (net/ipv4/af_inet.c:1539) dev_gro_receive (net/core/gro.c:515) gro_receive_skb (net/core/gro.c:633) cpu_map_kthread_run (kernel/bpf/cpumap.c:395) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) ret_from_fork_asm (arch/x86/entry/entry_64.S:255) Kernel panic - not syncing: KASAN: panic_on_warn set ...
Which versions are affected by CVE-2026-81002?
How do I fix CVE-2026-81002?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-81002 being exploited?
There is no known exploitation of CVE-2026-81002 in the wild and no public exploit code.
Sources
Also known as AZL-100196, BELL-CVE-2026-81002, DEBIAN-CVE-2026-81002, GHSA-w4xj-mpx6-w45f, UBUNTU-CVE-2026-81002.