# CVE-2022-48969: xen-netfront: Fix NULL sring after live migration

> A NULL pointer dereference in the Linux kernel's xen-netfront driver can cause a system crash during live migration if busy polling is enabled.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Oct 2024
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-48969, GHSA-h4qj-qcw9-2w6h, UBUNTU-CVE-2022-48969

## What is CVE-2022-48969?

CVE-2022-48969 is a medium-severity vulnerability in Linux kernel, published on 21 Oct 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

xen-netfront: Fix NULL sring after live migration

A NAPI is setup for each network sring to poll data to kernel
The sring with source host is destroyed before live migration and
new sring with target host is setup after live migration.
The NAPI for the old sring is not deleted until setup new sring
with target host after migration. With busy_poll/busy_read enabled,
the NAPI can be polled before got deleted when resume VM.

BUG: unable to handle kernel NULL pointer dereference at
0000000000000008
IP: xennet_poll+0xae/0xd20
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
Call Trace:
 finish_task_switch+0x71/0x230
 timerqueue_del+0x1d/0x40
 hrtimer_try_to_cancel+0xb5/0x110
 xennet_alloc_rx_buffers+0x2a0/0x2a0
 napi_busy_loop+0xdb/0x270
 sock_poll+0x87/0x90
 do_sys_poll+0x26f/0x580
 tracing_map_insert+0x1d4/0x2f0
 event_hist_trigger+0x14a/0x260

 finish_task_switch+0x71/0x230
 __schedule+0x256/0x890
 recalc_sigpending+0x1b/0x50
 xen_sched_clock+0x15/0x20
 __rb_reserve_next+0x12d/0x140
 ring_buffer_lock_reserve+0x123/0x3d0
 event_triggers_call+0x87/0xb0
 trace_event_buffer_commit+0x1c4/0x210
 xen_clocksource_get_cycles+0x15/0x20
 ktime_get_ts64+0x51/0xf0
 SyS_ppoll+0x160/0x1a0
 SyS_ppoll+0x160/0x1a0
 do_syscall_64+0x73/0x130
 entry_SYSCALL_64_after_hwframe+0x41/0xa6
...
RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900
CR2: 0000000000000008
---[ end trace f8601785b354351c ]---

xen frontend should remove the NAPIs for the old srings before live
migration as the bond srings are destroyed

There is a tiny window between the srings are set to NULL and
the NAPIs are disabled, It is safe as the NAPI threads are still
frozen at that time

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-48969?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-48969?

Apply the vendor's patch.

## Is CVE-2022-48969 being exploited?

There is no known exploitation of CVE-2022-48969 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-48969 and fix it if it is affected.

What it is: CVE-2022-48969 is a medium-severity vulnerability in Linux kernel, published on 21 Oct 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-48969 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2022-48969/ (Markdown: https://insights.sbomify.com/CVE-2022-48969/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-48969
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-48969
- OSV: https://osv.dev/vulnerability/CVE-2022-48969

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-48969/
Summaries are generated and may contain mistakes; the official description above is the record.