# CVE-2026-98937: perf/core: Check kernel access when kernel callchains are requested


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Oct 2026
- **Updated:** 26 Oct 2026
- **Also known as:** AZL-110729, BELL-CVE-2026-98937, DEBIAN-CVE-2026-98937, GHSA-5cg4-h7ff-5xr5, UBUNTU-CVE-2026-98937

## What is CVE-2026-98937?

CVE-2026-98937 is a vulnerability in Linux, published on 23 Oct 2026. 

### Official description

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

perf/core: Check kernel access when kernel callchains are requested

perf_event_open() currently gates perf_allow_kernel() only on
!attr.exclude_kernel.

However, users can still request kernel callchain collection with
attr.exclude_callchain_kernel == 0 even when attr.exclude_kernel == 1.
That still requires kernel profiling privilege, but the existing check
does not enforce it.

Update the permission check to call perf_allow_kernel() when either
kernel sampling is requested or kernel callchains are requested.

This keeps permission checks aligned with requested data and prevents
unprivileged use of kernel callchain capture.

## Which versions are affected by CVE-2026-98937?


## How do I fix CVE-2026-98937?

Upgrade to a fixed version.

## Is CVE-2026-98937 being exploited?

There is no known exploitation of CVE-2026-98937 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98937 and fix it if it is affected.

What it is: CVE-2026-98937 is a vulnerability in Linux, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-98937 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-2026-98937/ (Markdown: https://insights.sbomify.com/CVE-2026-98937/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98937
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98937
- OSV: https://osv.dev/vulnerability/CVE-2026-98937

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98937/
Summaries are generated and may contain mistakes; the official description above is the record.