# CVE-2026-52934: batman-adv: tvlv: reject oversized TVLV packets

> An integer overflow in the batman-adv kernel module allows attackers to corrupt kernel memory, potentially leading to code execution or privilege escalation.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 24 Jun 2026
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-90938, BELL-CVE-2026-52934, DEBIAN-CVE-2026-52934, GHSA-w473-pp3w-rqc2, ROOT-OS-DEBIAN-11-CVE-2026-52934, ROOT-OS-DEBIAN-12-CVE-2026-52934, ROOT-OS-UBUNTU-2204-CVE-2026-52934, ROOT-OS-UBUNTU-2404-CVE-2026-52934, UBUNTU-CVE-2026-52934

## What is CVE-2026-52934?

CVE-2026-52934 is a high-severity vulnerability in Linux kernel, published on 24 Jun 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: tvlv: reject oversized TVLV packets

batadv_tvlv_container_ogm_append() builds a TVLV packet section from
the tvlv.container_list. The total size of this section is computed by
batadv_tvlv_container_list_size(), which sums the sizes of all registered
containers.

The return type and accumulator in batadv_tvlv_container_list_size() were
u16. If the accumulated size exceeds U16_MAX, the value wraps around,
causing the subsequent allocation in batadv_tvlv_container_ogm_append()
to be undersized. The memcpy-style copy that follows would then write
beyond the end of the allocated buffer, corrupting kernel memory.

Fix this by widening the return type of batadv_tvlv_container_list_size()
to size_t. In batadv_tvlv_container_ogm_append(), check the computed length
against U16_MAX before proceeding, and bail out as if the allocation had
failed when the limit is exceeded.

## Which versions are affected by CVE-2026-52934?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-52934?

Apply the vendor's patch.

## Is CVE-2026-52934 being exploited?

There is no known exploitation of CVE-2026-52934 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-2026-52934 and fix it if it is affected.

What it is: CVE-2026-52934 is a high-severity vulnerability in Linux kernel, published on 24 Jun 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-2026-52934 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-2026-52934/ (Markdown: https://insights.sbomify.com/CVE-2026-52934/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52934
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52934
- OSV: https://osv.dev/vulnerability/CVE-2026-52934

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52934/
Summaries are generated and may contain mistakes; the official description above is the record.