CVE intelligence

CVE-2026-99218

Vulnerability intelligence

Published Nov 2, 2026Sources checked Nov 5, 2026

7.0HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-99218 and is rated High severity with a CVSS score of 7.0. 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: Nov 4, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-99218?

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

coredump: hold RCU while releasing parked threads

coredump_finish() releases the parked threads by clearing ->task in their core_thread entry and calling wake_up_process() on each of them. It does that without holding a reference on the task and without being inside rcu.

But calling wake_up_process(task) without rcu here isn't safe. A parked thread doesn't need that wakeup to leave.

A spurious wakeup or a preemption after the store is enough for the task to go away.

So if the coredump client is preempted between the store and wake_up_process() the thread can exit and be freed in the meantime and try_to_wake_up() takes pi_lock in freed memory.

Hold rcu across the loop.

Source: NVD