CVE-2026-80556

Local privilege escalation via teardown workqueue race

Published Aug 26, 2026 · Updated Aug 27, 2026

Use-after-free in the atmel-mci driver in affected Linux kernel branches allows local users to corrupt kernel memory during removal. atmci_remove returns while bh_work can remain queued or running, so devm releases host before atmci_work_func finishes dereferencing it. A local low-privileged user with /dev/mmcblk access must overlap I/O with driver teardown, enabling privilege escalation or a system crash.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the atmel-mci driver in affected Linux kernel branches allows local users to corrupt kernel memory during removal. atmci_remove returns while bh_work can remain queued or running, so devm releases host before atmci_work_func finishes dereferencing it. A local low-privileged user with /dev/mmcblk access must overlap I/O with driver teardown, enabling privilege escalation or a system crash.

The record

CVE
CVE-2026-80556
Published
Aug 26, 2026
Updated
Aug 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-825, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.6.27
  2. Affected versionversion=7d2be0749a59096a334c94dc48f43294193cb8ed <22aecf6c4721727a2f724ca0438bc7d4b609bf3f
  3. Affected versionversion=7d2be0749a59096a334c94dc48f43294193cb8ed <7599a73ff66d195a908f5d88b427933a9fb1c02a
  4. Affected versionversion=7d2be0749a59096a334c94dc48f43294193cb8ed <b5060ff2f5460795a3e9f7cdf5052aa42f96ff81
  5. Affected versionversion=7d2be0749a59096a334c94dc48f43294193cb8ed <c125ee35a49a0518521b52b27631eef061b8719a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.27; version=7d2be0749a59096a334c94dc48f43294193cb8ed <22aecf6c4721727a2f724ca0438bc7d4b609bf3f; version=7d2be0749a59096a334c94dc48f43294193cb8ed <7599a73ff66d195a908f5d88b427933a9fb1c02a; version=7d2be0749a59096a334c94dc48f43294193cb8ed <b5060ff2f5460795a3e9f7cdf5052aa42f96ff81; version=7d2be0749a59096a334c94dc48f43294193cb8ed <c125ee35a49a0518521b52b27631eef061b8719a

Published CVSS scores

7.8Linux CVE TeamCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-825Expired Pointer Dereference
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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