# CVE-2026-98247: Bluetooth: hci_codec: validate vendor codec count length

> A missing length check in the Linux kernel Bluetooth codec parser allows a local attacker to cause a denial of service via out-of-bounds read.

- **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:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106200, BELL-CVE-2026-98247, DEBIAN-CVE-2026-98247, GHSA-w49g-pfqv-m398, UBUNTU-CVE-2026-98247

## What is CVE-2026-98247?

CVE-2026-98247 is a denial of service vulnerability in Linux, published on 6 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:

Bluetooth: hci_codec: validate vendor codec count length

The Read Local Supported Codecs parsers consume the variable-sized
standard codec array before parsing the vendor codec count.  Although the
initial reply-size check includes a vendor count byte in the fixed layout,
it does not guarantee that the byte remains after the standard codec array.

If a controller reply ends immediately after that array, calculating the
vendor codec array size reads vnd_codecs->num beyond the skb data.  Use
skb_pull_data() to validate and consume each codec header before using its
count in both command variants.

## Which versions are affected by CVE-2026-98247?


## How do I fix CVE-2026-98247?

Apply the vendor's patch.

## Is CVE-2026-98247 being exploited?

There is no known exploitation of CVE-2026-98247 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98247 and fix it if it is affected.

What it is: CVE-2026-98247 is a denial of service vulnerability in Linux, published on 6 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-2026-98247 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-2026-98247/ (Markdown: https://insights.sbomify.com/CVE-2026-98247/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98247
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98247
- OSV: https://osv.dev/vulnerability/CVE-2026-98247

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98247/
Summaries are generated and may contain mistakes; the official description above is the record.