# CVE-2026-64420: mfd: cros_ec: Delay dev_set_drvdata() until probe success

> A use-after-free in the Linux kernel cros_ec driver allows attackers to cause a denial of service or potentially execute code via stale pointers.

- **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/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:** 25 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-64420, DEBIAN-CVE-2026-64420, GHSA-wgwq-6fx3-368g, ROOT-OS-DEBIAN-12-CVE-2026-64420, ROOT-OS-UBUNTU-2204-CVE-2026-64420, UBUNTU-CVE-2026-64420

## What is CVE-2026-64420?

CVE-2026-64420 is a high-severity use after free vulnerability in Linux kernel, published on 25 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:

mfd: cros_ec: Delay dev_set_drvdata() until probe success

If ec_device_probe() fails, cros_ec_class_release releases memory for the
cros_ec_dev structure. However, because the drvdata was already set,
sub-drivers like cros_ec_typec can still retrieve the stale pointer via the
platform device. This leads to a use-after-free when cros_ec_typec attempts
to access &typec->ec->ec->dev on a device that has already been released.
Move dev_set_drvdata() to ensure that the pointer is only made available
once all initialization steps have succeeded.

 sysfs: cannot create duplicate filename '/class/chromeos/cros_ec'
 Call trace:
  sysfs_do_create_link_sd+0x94/0xdc
  sysfs_create_link+0x30/0x44
  device_add_class_symlinks+0x90/0x13c
  device_add+0xf0/0x50c
  ec_device_probe+0x150/0x4f0
  platform_probe+0xa0/0xe0
 ...
 BUG: KASAN: invalid-access in __memcpy+0x44/0x230
 Write at addr f5ffff809e2d33ac by task kworker/u32:5/125
 Pointer tag: [f5], memory tag: [fe]
 Tainted : [W]=WARN, [O]=OOT_MODULE
 Hardware name: Google Navi unprovisioned 0x7FFFFFFF/sku0 board/sku3
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  __memcpy+0x44/0x230
  cros_ec_check_features+0x60/0xcc [cros_ec_proto]
  cros_typec_probe+0xe8/0x6e0 [cros_ec_typec]
  platform_probe+0xa0/0xe0

Weakness: CWE-476 (NULL Pointer Dereference), CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-64420?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64420?

Apply the vendor's patch.

## Is CVE-2026-64420 being exploited?

There is no known exploitation of CVE-2026-64420 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-2026-64420 and fix it if it is affected.

What it is: CVE-2026-64420 is a high-severity use after free vulnerability in Linux kernel, published on 25 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-2026-64420 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-2026-64420/ (Markdown: https://insights.sbomify.com/CVE-2026-64420/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64420
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64420
- OSV: https://osv.dev/vulnerability/CVE-2026-64420

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64420/
Summaries are generated and may contain mistakes; the official description above is the record.