# CVE-2026-98458: Bluetooth: ISO: release unused CIS holds after channel attach

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

- **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-109373, BELL-CVE-2026-98458, DEBIAN-CVE-2026-98458, GHSA-9rg4-gm9p-59qp, UBUNTU-CVE-2026-98458

## What is CVE-2026-98458?

CVE-2026-98458 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: release unused CIS holds after channel attach

hci_bind_cis() and hci_connect_cis() return one hci_conn hold for the
ISO layer.  A new channel association consumes that hold, which is
eventually released by iso_conn_free().

There are two cases where iso_chan_add() does not create an association:
it returns success when the socket is already attached to the same
iso_conn, and it returns -EBUSY when another socket is attached.  The
hold returned for the current call is unused in both cases.  This occurs
when deferred setup calls iso_connect_cis() again for its existing
socket, or when another socket attempts to reuse the CIS.

Detect the idempotent case while the connection is locked and release
the unused hold after iso_chan_add().  Also release it on -EBUSY.  Do not
drop it for other errors: a newly allocated iso_conn releases the
transferred hold when its last temporary reference is put.

## Which versions are affected by CVE-2026-98458?


## How do I fix CVE-2026-98458?

Apply the vendor's patch.

## Is CVE-2026-98458 being exploited?

There is no known exploitation of CVE-2026-98458 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98458 and fix it if it is affected.

What it is: CVE-2026-98458 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-2026-98458 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-2026-98458/ (Markdown: https://insights.sbomify.com/CVE-2026-98458/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98458
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98458
- OSV: https://osv.dev/vulnerability/CVE-2026-98458

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98458/
Summaries are generated and may contain mistakes; the official description above is the record.