# CVE-2026-23213: drm/amd/pm: Disable MMIO access during SMU Mode 1 reset

> A race condition in the AMD GPU driver during SMU Mode 1 reset can cause system hangs or panics due to invalid MMIO access.

- **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:** 18 Feb 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-77858, BELL-CVE-2026-23213, DEBIAN-CVE-2026-23213, GHSA-h85r-3jrw-9546, ROOT-OS-DEBIAN-11-CVE-2026-23213, ROOT-OS-DEBIAN-12-CVE-2026-23213, ROOT-OS-UBUNTU-2204-CVE-2026-23213, ROOT-OS-UBUNTU-2404-CVE-2026-23213, UBUNTU-CVE-2026-23213

## What is CVE-2026-23213?

CVE-2026-23213 is a medium-severity vulnerability in Linux kernel, published on 18 Feb 2026. 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:

drm/amd/pm: Disable MMIO access during SMU Mode 1 reset

During Mode 1 reset, the ASIC undergoes a reset cycle and becomes
temporarily inaccessible via PCIe. Any attempt to access MMIO registers
during this window (e.g., from interrupt handlers or other driver threads)
can result in uncompleted PCIe transactions, leading to NMI panics or
system hangs.

To prevent this, set the `no_hw_access` flag to true immediately after
triggering the reset. This signals other driver components to skip
register accesses while the device is offline.

A memory barrier `smp_mb()` is added to ensure the flag update is
globally visible to all cores before the driver enters the sleep/wait
state.

(cherry picked from commit 7edb503fe4b6d67f47d8bb0dfafb8e699bb0f8a4)

## Which versions are affected by CVE-2026-23213?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23213?

Apply the vendor's patch.

## Is CVE-2026-23213 being exploited?

There is no known exploitation of CVE-2026-23213 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-2026-23213 and fix it if it is affected.

What it is: CVE-2026-23213 is a medium-severity vulnerability in Linux kernel, published on 18 Feb 2026. 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-2026-23213 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-2026-23213/ (Markdown: https://insights.sbomify.com/CVE-2026-23213/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23213
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23213
- OSV: https://osv.dev/vulnerability/CVE-2026-23213

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23213/
Summaries are generated and may contain mistakes; the official description above is the record.