# 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.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-100196, BELL-CVE-2026-81002, DEBIAN-CVE-2026-81002, GHSA-w4xj-mpx6-w45f, UBUNTU-CVE-2026-81002

## 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.

## Is CVE-2026-81002 being exploited?

There is no known exploitation of CVE-2026-81002 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81002 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-81002 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-81002/ (Markdown: https://insights.sbomify.com/CVE-2026-81002/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81002
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81002
- OSV: https://osv.dev/vulnerability/CVE-2026-81002

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-81002/
Summaries are generated and may contain mistakes; the official description above is the record.