# CVE-2026-64094: batman-adv: bla: avoid NULL-ptr deref for claim via dropped interface

> A race condition in the batman-adv kernel module can cause a NULL pointer dereference, leading to a system crash or denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2026
- **Updated:** 19 Jul 2026
- **Also known as:** BELL-CVE-2026-64094, DEBIAN-CVE-2026-64094, GHSA-7pc5-4w4m-mhg6, ROOT-OS-UBUNTU-2204-CVE-2026-64094, UBUNTU-CVE-2026-64094

## What is CVE-2026-64094?

CVE-2026-64094 is a medium-severity vulnerability in Linux kernel, published on 19 Jul 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:

batman-adv: bla: avoid NULL-ptr deref for claim via dropped interface

Without rtnl_lock held, a hardif might be retrieved as primary interface of
a meshif, but then (while operating on this interface) getting decoupled
from the mesh interface. In this case, the meshif still exists but the
pointer from the primary hardif to the meshif is set to NULL.

The mesh_iface must be checked first to be non-NULL before continuing to
send an ARP request using meshif.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-64094?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64094?

Apply the vendor's patch.

## Is CVE-2026-64094 being exploited?

There is no known exploitation of CVE-2026-64094 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64094 and fix it if it is affected.

What it is: CVE-2026-64094 is a medium-severity vulnerability in Linux kernel, published on 19 Jul 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-2026-64094 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-64094/ (Markdown: https://insights.sbomify.com/CVE-2026-64094/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64094
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64094
- OSV: https://osv.dev/vulnerability/CVE-2026-64094

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64094/
Summaries are generated and may contain mistakes; the official description above is the record.