CVE intelligence

CVE-2021-47324

Vulnerability intelligence

Published May 21, 2024Sources checked Nov 14, 2026

8.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2021-47324 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Aug 12, 2026

CBL-Mariner Releases

Vendor-listed releases

5.15.179.1-1
6.6.85.1-1

CISA KEVNot listedBased on the latest collected catalog

EPSS1.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2021-47324?

In the Linux kernel, the following vulnerability has been resolved:

watchdog: Fix possible use-after-free in wdt_startup()

This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes.

This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free.

Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Source: NVD