# CVE-2026-98459: Bluetooth: ISO: balance the parent hold in hci_bind_bis()

> A use-after-free in the Linux kernel Bluetooth ISO subsystem allows attackers to cause denial of service or potentially execute code via crafted Bluetooth connections.

- **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:** AZL-109398, BELL-CVE-2026-98459, DEBIAN-CVE-2026-98459, GHSA-w8fc-m2x5-xcfp, UBUNTU-CVE-2026-98459

## What is CVE-2026-98459?

CVE-2026-98459 is an use after free 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:

Bluetooth: ISO: balance the parent hold in hci_bind_bis()

hci_conn_link() takes a lifetime reference to its parent with
hci_conn_get(), but only takes an operational hold on the child.
hci_conn_unlink() later balances both a hold and a reference on the
parent.

The SCO and CIS paths pass a parent acquired from a connect helper, so
it already has a hold. For an additional BIS, hci_bind_bis() obtains the
parent from hci_conn_hash_lookup_big(), which returns a bare pointer.
Unlinking the child then drops the parent's existing hold and can
schedule it for disconnection while its socket is still using it.

Take a hold on the parent before linking it and drop that hold if linking
fails. A successful link transfers the hold to hci_conn_unlink().

## Which versions are affected by CVE-2026-98459?


## How do I fix CVE-2026-98459?

Apply the vendor's patch.

## Is CVE-2026-98459 being exploited?

There is no known exploitation of CVE-2026-98459 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98459 and fix it if it is affected.

What it is: CVE-2026-98459 is an use after free 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-2026-98459 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-2026-98459/ (Markdown: https://insights.sbomify.com/CVE-2026-98459/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98459
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98459
- OSV: https://osv.dev/vulnerability/CVE-2026-98459

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98459/
Summaries are generated and may contain mistakes; the official description above is the record.