# CVE-2021-47019: mt76: mt7921: fix possible invalid register access

> A race condition in the mt7921 Wi-Fi driver during system suspend can cause invalid register access, leading to a kernel panic and denial of service.

- **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:** No
- **Published:** 28 Feb 2024
- **Updated:** 11 May 2026
- **Also known as:** GHSA-gc58-f6gq-w9xv, UBUNTU-CVE-2021-47019

## What is CVE-2021-47019?

CVE-2021-47019 is a medium-severity vulnerability in Linux kernel, published on 28 Feb 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:

mt76: mt7921: fix possible invalid register access

Disable the interrupt and synchronze for the pending irq handlers to ensure
the irq tasklet is not being scheduled after the suspend to avoid the
possible invalid register access acts when the host pcie controller is
suspended.

[17932.910534] mt7921e 0000:01:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 21375 usecs
[17932.910590] pcieport 0000:00:00.0: calling pci_pm_suspend+0x0/0x22c @ 18565, parent: pci0000:00
[17932.910602] pcieport 0000:00:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 8 usecs
[17932.910671] mtk-pcie 11230000.pcie: calling platform_pm_suspend+0x0/0x60 @ 22783, parent: soc
[17932.910674] mtk-pcie 11230000.pcie: platform_pm_suspend+0x0/0x60 returned 0 after 0 usecs

...

17933.615352] x1 : 00000000000d4200 x0 : ffffff8269ca2300
[17933.620666] Call trace:
[17933.623127]  mt76_mmio_rr+0x28/0xf0 [mt76]
[17933.627234]  mt7921_rr+0x38/0x44 [mt7921e]
[17933.631339]  mt7921_irq_tasklet+0x54/0x1d8 [mt7921e]
[17933.636309]  tasklet_action_common+0x12c/0x16c
[17933.640754]  tasklet_action+0x24/0x2c
[17933.644418]  __do_softirq+0x16c/0x344
[17933.648082]  irq_exit+0xa8/0xac
[17933.651224]  scheduler_ipi+0xd4/0x148
[17933.654890]  handle_IPI+0x164/0x2d4
[17933.658379]  gic_handle_irq+0x140/0x178
[17933.662216]  el1_irq+0xb8/0x180
[17933.665361]  cpuidle_enter_state+0xf8/0x204
[17933.669544]  cpuidle_enter+0x38/0x4c
[17933.673122]  do_idle+0x1a4/0x2a8
[17933.676352]  cpu_startup_entry+0x24/0x28
[17933.680276]  rest_init+0xd4/0xe0
[17933.683508]  arch_call_rest_init+0x10/0x18
[17933.687606]  start_kernel+0x340/0x3b4
[17933.691279] Code: aa0003f5 d503201f f953eaa8 8b344108 (b9400113)
[17933.697373] ---[ end trace a24b8e26ffbda3c5 ]---
[17933.767846] Kernel panic - not syncing: Fatal exception in interrupt

## Which versions are affected by CVE-2021-47019?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2021-47019?

No fix has been published for CVE-2021-47019 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-47019 being exploited?

There is no known exploitation of CVE-2021-47019 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-2021-47019 and fix it if it is affected.

What it is: CVE-2021-47019 is a medium-severity vulnerability in Linux kernel, published on 28 Feb 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-2021-47019 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-2021-47019/ (Markdown: https://insights.sbomify.com/CVE-2021-47019/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47019
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47019
- OSV: https://osv.dev/vulnerability/CVE-2021-47019

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47019/
Summaries are generated and may contain mistakes; the official description above is the record.