# CVE-2026-98648: s390/uv: Prevent potential out-of-bounds read

> An out-of-bounds read in the Linux kernel s390 UV driver allows attackers to read memory or cause a crash when handling many secrets.

- **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:** 18 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-98648, DEBIAN-CVE-2026-98648, GHSA-88ff-f8f3-f4qh, UBUNTU-CVE-2026-98648

## What is CVE-2026-98648?

CVE-2026-98648 is a memory corruption vulnerability in Linux, published on 18 Oct 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:

s390/uv: Prevent potential out-of-bounds read

When the system has more than 85 secrets, the uv_secret_list struct
array only holds up to 85 items per page, resulting in an out of bounds
read in find_secret_in_page if the targeted secret is in the next page
or not stored at all.

Fix this by looping over the number of stored secrets which is the
per sub-list count of stored secrets and not the overall count.

## Which versions are affected by CVE-2026-98648?


## How do I fix CVE-2026-98648?

Apply the vendor's patch.

## Is CVE-2026-98648 being exploited?

There is no known exploitation of CVE-2026-98648 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98648 and fix it if it is affected.

What it is: CVE-2026-98648 is a memory corruption vulnerability in Linux, published on 18 Oct 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-2026-98648 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-2026-98648/ (Markdown: https://insights.sbomify.com/CVE-2026-98648/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98648
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98648
- OSV: https://osv.dev/vulnerability/CVE-2026-98648

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98648/
Summaries are generated and may contain mistakes; the official description above is the record.