# CVE-2026-64030: wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs

> A remote attacker can crash the Linux kernel by sending a crafted WiFi 7 action frame, causing an out-of-bounds read in the mac80211 subsystem.

- **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:** 19 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-64030, DEBIAN-CVE-2026-64030, GHSA-2j8j-jv7c-wm9j, UBUNTU-CVE-2026-64030

## What is CVE-2026-64030?

CVE-2026-64030 is a high-severity memory corruption 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:

wifi: mac80211: bounds-check link_id in ieee80211_ml_epcs

IEEE80211_MLE_STA_EPCS_CONTROL_LINK_ID is 0x000f, so link_id extracted
from a PRIO_ACCESS ML element PER_STA_PROFILE subelement can be 0..15.
sdata->link[] has IEEE80211_MLD_MAX_NUM_LINKS (15) entries (indices 0..14),
making index 15 out-of-bounds.

A connected WiFi 7 AP can trigger this by sending an EPCS Enable Response
action frame with a PER_STA_PROFILE subelement where link_id = 15.  The
unsolicited-notification path (dialog_token = 0) is reachable any time
EPCS is already enabled, without any prior client request.

sdata->link[15] reads into the first word of sdata->activate_links_work
(a wiphy_work whose embedded list_head is non-NULL after INIT_LIST_HEAD),
so the NULL check on the result does not catch the invalid access.  The
garbage pointer is then passed to ieee80211_sta_wmm_params(), which
dereferences link->sdata and crashes the kernel.

The same class of bug was fixed for ieee80211_ml_reconfiguration() by
commit 162d331d833d ("wifi: mac80211: bounds-check link_id in
ieee80211_ml_reconfiguration").

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-64030?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64030?

Apply the vendor's patch.

## Is CVE-2026-64030 being exploited?

There is no known exploitation of CVE-2026-64030 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-2026-64030 and fix it if it is affected.

What it is: CVE-2026-64030 is a high-severity memory corruption 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-2026-64030 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-2026-64030/ (Markdown: https://insights.sbomify.com/CVE-2026-64030/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64030
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64030
- OSV: https://osv.dev/vulnerability/CVE-2026-64030

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64030/
Summaries are generated and may contain mistakes; the official description above is the record.