# CVE-2025-38646: wifi: rtw89: avoid NULL dereference when RX problematic packet on unsupported 6 GHz band

> A rare race condition in the rtw89 WiFi driver causes a kernel crash when processing specific packets on unsupported 6 GHz bands.

- **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:** 22 Aug 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-66650, BELL-CVE-2025-38646, DEBIAN-CVE-2025-38646, GHSA-5vg6-qhc8-fjr6, ROOT-OS-DEBIAN-13-CVE-2025-38646, ROOT-OS-UBUNTU-2404-CVE-2025-38646, UBUNTU-CVE-2025-38646

## What is CVE-2025-38646?

CVE-2025-38646 is a medium-severity vulnerability in Linux kernel, published on 22 Aug 2025. 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:

wifi: rtw89: avoid NULL dereference when RX problematic packet on unsupported 6 GHz band

With a quite rare chance, RX report might be problematic to make SW think
a packet is received on 6 GHz band even if the chip does not support 6 GHz
band actually. Since SW won't initialize stuffs for unsupported bands, NULL
dereference will happen then in the sequence, rtw89_vif_rx_stats_iter() ->
rtw89_core_cancel_6ghz_probe_tx(). So, add a check to avoid it.

The following is a crash log for this case.

 BUG: kernel NULL pointer dereference, address: 0000000000000032
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 1 PID: 1907 Comm: irq/131-rtw89_p Tainted: G     U             6.6.56-05896-g89f5fb0eb30b #1 (HASH:1400 4)
 Hardware name: Google Telith/Telith, BIOS Google_Telith.15217.747.0 11/12/2024
 RIP: 0010:rtw89_vif_rx_stats_iter+0xd2/0x310 [rtw89_core]
 Code: 4c 89 7d c8 48 89 55 c0 49 8d 44 24 02 48 89 45 b8 45 31 ff eb 11
 41 c6 45 3a 01 41 b7 01 4d 8b 6d 00 4d 39 f5 74 42 8b 43 10 <41> 33 45
 32 0f b7 4b 14 66 41 33 4d 36 0f b7 c9 09 c1 74 d8 4d 85
 RSP: 0018:ffff9f3080138ca0 EFLAGS: 00010246
 RAX: 00000000b8bf5770 RBX: ffff91b5e8c639c0 RCX: 0000000000000011
 RDX: ffff91b582de1be8 RSI: 0000000000000000 RDI: ffff91b5e8c639e6
 RBP: ffff9f3080138d00 R08: 0000000000000000 R09: 0000000000000000
 R10: ffff91b59de70000 R11: ffffffffc069be50 R12: ffff91b5e8c639e4
 R13: 0000000000000000 R14: ffff91b5828020b8 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff91b8efa40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000032 CR3: 00000002bf838000 CR4: 0000000000750ee0
 PKRU: 55555554
 Call Trace:
  <IRQ>
  ? __die_body+0x68/0xb0
  ? page_fault_oops+0x379/0x3e0
  ? exc_page_fault+0x4f/0xa0
  ? asm_exc_page_fault+0x22/0x30
  ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)]
  ? rtw89_vif_rx_stats_iter+0xd2/0x310 [rtw89_core (HASH:1400 5)]
  __iterate_interfaces+0x59/0x110 [mac80211 (HASH:1400 6)]
  ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)]
  ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)]
  ieee80211_iterate_active_interfaces_atomic+0x36/0x50 [mac80211 (HASH:1400 6)]
  rtw89_core_rx_to_mac80211+0xfd/0x1b0 [rtw89_core (HASH:1400 5)]
  rtw89_core_rx+0x43a/0x980 [rtw89_core (HASH:1400 5)]

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-38646?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-38646?

Apply the vendor's patch.

## Is CVE-2025-38646 being exploited?

There is no known exploitation of CVE-2025-38646 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-2025-38646 and fix it if it is affected.

What it is: CVE-2025-38646 is a medium-severity vulnerability in Linux kernel, published on 22 Aug 2025. 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-2025-38646 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-2025-38646/ (Markdown: https://insights.sbomify.com/CVE-2025-38646/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38646
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38646
- OSV: https://osv.dev/vulnerability/CVE-2025-38646

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38646/
Summaries are generated and may contain mistakes; the official description above is the record.
