CVE intelligence

CVE-2026-90066

Vulnerability intelligence

Published Sep 17, 2026Sources checked Nov 11, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-90066. 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: Oct 21, 2026

Release Notes

Vendor-listed releases

6.6.157.1-1

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-90066?

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

samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify

ftrace_direct_multi_init() assigns kthread_run()'s return value to simple_tsk without an IS_ERR() check. When kthread_run() fails it returns ERR_PTR(-ENOMEM), but init still returns 0, so the module loads with simple_tsk holding an error pointer.

On unload, ftrace_direct_multi_exit() then passes that ERR_PTR to kthread_stop(), leading to a null-pointer-dereference.

Check the return value of kthread_run() with IS_ERR(); on failure, unregister the ftrace direct call and propagate the error code.

Source: NVD