---
id: CVE-2026-98826
title: >-
  kernel: kernel: Denial of service via use-after-free in the AC100 RTC driver
  (CVE-2026-98826)
summary: >-
  A flaw was found in the Linux kernel's AC100 Real-Time Clock (RTC) driver. If
  device initialization fails during driver probing, unmanaged clock provider
  references remain registered in global system lists while their underlying
  memory is …
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-416
vendor: Red Hat
product: Red Hat Enterprise Linux 10
affected:
  - enterprise_linux 10
published: '2026-10-18'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T06:08:44+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98826.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98826.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-98826'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2555253'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-98826'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-98826'
  - url: 'https://git.kernel.org/stable/c/12bcd20d76703ee2baf52224d287b7fea096b12f'
  - url: 'https://git.kernel.org/stable/c/55ca60ba336632349f7c4585d22ba74ae355b7ce'
  - url: 'https://git.kernel.org/stable/c/9cff19ddd7f90c1f572a0f83cfc41de8f8dcbcd8'
  - url: 'https://git.kernel.org/stable/c/fcf0b58e976e83adf246b014518e49c662b96f5e'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.002
epssPercentile: 0.09736
ingestedAt: '2026-10-18T16:47:32.472Z'
---

## Overview

A flaw was found in the Linux kernel's AC100 Real-Time Clock (RTC) driver. If device initialization fails during driver probing, unmanaged clock provider references remain registered in global system lists while their underlying memory is released. Subsequent lookups referencing the affected device can access this freed memory, triggering a use-after-free condition that can lead to a system crash and Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98826.json)

**kernel: kernel: Denial of service via use-after-free in the AC100 RTC driver** — rated Moderate by Red Hat. Released 2026-10-18, updated 2026-10-20.

Affected:

- Red Hat Enterprise Linux 10

No fix planned:

- Red Hat Enterprise Linux 10

## Remediation

Fix deferred

Workarounds / mitigations:

- Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.