# CVE-2026-80623: coresight: ete: Always save state on power down

> A Linux kernel bug in Coresight ETE handling causes system warnings and potential instability during CPU power down, requiring a kernel patch.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 Aug 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-98054, BELL-CVE-2026-80623, DEBIAN-CVE-2026-80623, GHSA-6v36-jxjj-2vq8, UBUNTU-CVE-2026-80623

## What is CVE-2026-80623?

CVE-2026-80623 is a denial of service vulnerability in Linux, published on 28 Aug 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:

coresight: ete: Always save state on power down

System register ETMs and ETE are unlikely to be preserved on CPU power
down. The ETE DT binding also never documented
"arm,coresight-loses-context-with-cpu" so nobody would have legitimately
been able to use that binding to fix it and ACPI has no such binding at
all.

Fix it by hard coding the setting for sysreg ETMs (ETE is always sysreg)
or ACPI boots. Use a local variable when setting up save_state so that
it's immune to concurrent probing when devices have different
configurations which is an issue with modifying the global.

This fixes the following error when using Coresight with ACPI on the FVP
which supports CPU PM:

  coresight ete0: External agent took claim tag
  WARNING: drivers/hwtracing/coresight/coresight-core.c:248 at coresight_disclaim_device_unlocked+0xe0/0xe8, CPU#0: perf/117

## Which versions are affected by CVE-2026-80623?


## How do I fix CVE-2026-80623?

Apply the vendor's patch.

## Is CVE-2026-80623 being exploited?

There is no known exploitation of CVE-2026-80623 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80623 and fix it if it is affected.

What it is: CVE-2026-80623 is a denial of service vulnerability in Linux, published on 28 Aug 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-2026-80623 in the wild and no public exploit code.

Affected product: Linux. 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-2026-80623/ (Markdown: https://insights.sbomify.com/CVE-2026-80623/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80623
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80623
- OSV: https://osv.dev/vulnerability/CVE-2026-80623

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80623/
Summaries are generated and may contain mistakes; the official description above is the record.