# CVE-2026-64116: ipv6: ioam: add NULL check for idev in ipv6_hop_ioam()

> A NULL pointer dereference in the Linux kernel's IPv6 IOAM handling can cause a system crash during interface teardown.

- **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:** 19 Jul 2026
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2026-64116, DEBIAN-CVE-2026-64116, GHSA-6p6q-g32r-gx25, ROOT-OS-UBUNTU-2204-CVE-2026-64116, UBUNTU-CVE-2026-64116

## What is CVE-2026-64116?

CVE-2026-64116 is a high-severity vulnerability in Linux kernel, published on 19 Jul 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:

ipv6: ioam: add NULL check for idev in ipv6_hop_ioam()

Reported by Sashiko:

The function ipv6_hop_ioam() accesses
__in6_dev_get(skb->dev)->cnf.ioam6_enabled without validating the returned
idev pointer. Because addrconf_ifdown() can concurrently clear dev->ip6_ptr
via RCU, __in6_dev_get() can return NULL during interface teardown, which
could cause a NULL pointer dereference when processing an IOAM Hop-by-Hop
option.

Let's add a check and use SKB_DROP_REASON_IPV6DISABLED accordingly.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-64116?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64116?

Apply the vendor's patch.

## Is CVE-2026-64116 being exploited?

There is no known exploitation of CVE-2026-64116 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-2026-64116 and fix it if it is affected.

What it is: CVE-2026-64116 is a high-severity vulnerability in Linux kernel, published on 19 Jul 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-2026-64116 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-2026-64116/ (Markdown: https://insights.sbomify.com/CVE-2026-64116/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64116
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64116
- OSV: https://osv.dev/vulnerability/CVE-2026-64116

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64116/
Summaries are generated and may contain mistakes; the official description above is the record.