# CVE-2026-52981: neigh: let neigh_xmit take skb ownership

> A memory leak in the Linux kernel's neigh_xmit function can lead to resource exhaustion and denial of service when IPv6 is disabled.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Jun 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-52981, DEBIAN-CVE-2026-52981, GHSA-36qf-2q77-7jh9, ROOT-OS-DEBIAN-11-CVE-2026-52981, ROOT-OS-DEBIAN-12-CVE-2026-52981, ROOT-OS-UBUNTU-2204-CVE-2026-52981, ROOT-OS-UBUNTU-2404-CVE-2026-52981, UBUNTU-CVE-2026-52981

## What is CVE-2026-52981?

CVE-2026-52981 is a high-severity denial of service vulnerability in Linux kernel, published on 24 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

neigh: let neigh_xmit take skb ownership

neigh_xmit always releases the skb, except when no neighbour table is
found. But even the first added user of neigh_xmit (mpls) relied on
neigh_xmit to release the skb (or queue it for tx).

sashiko reported:
 If neigh_xmit() is called with an uninitialized neighbor table (for
 example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT
 and bypasses its internal out_kfree_skb error path.  Because the return
 value of neigh_xmit() is ignored here, does this leak the SKB?

Assume full ownership and remove the last code path that doesn't
xmit or free skb.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2026-52981?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-52981?

Apply the vendor's patch.

## Is CVE-2026-52981 being exploited?

There is no known exploitation of CVE-2026-52981 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-2026-52981 and fix it if it is affected.

What it is: CVE-2026-52981 is a high-severity denial of service vulnerability in Linux kernel, published on 24 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-52981 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-2026-52981/ (Markdown: https://insights.sbomify.com/CVE-2026-52981/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52981
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52981
- OSV: https://osv.dev/vulnerability/CVE-2026-52981

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52981/
Summaries are generated and may contain mistakes; the official description above is the record.