CVE intelligence

CVE-2026-89567

Vulnerability intelligence

Published Sep 11, 2026Sources checked Oct 30, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-89567. 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: Sep 24, 2026

Release Notes

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-2026-89567?

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

jbd2: bound shrinker scans by examined checkpoint buffers

The jbd2 shrinker currently accounts only checkpoint buffers that it successfully releases against nr_to_scan. Busy buffers therefore do not consume the scan budget.

If a checkpoint transaction contains mostly busy buffers, the shrinker can scan its entire checkpoint list while holding journal->j_list_lock. Large checkpoint lists can result in excessive lock hold times and leave other CPUs spinning on j_list_lock, causing soft lockups or RCU stalls.

Pass nr_to_scan into journal_shrink_one_cp_list() and decrement it for every buffer examined, including busy buffers. Pass NULL from checkpoint cleanup paths so their existing full-list behavior is preserved.

This restores the scan-budget semantics that existed before journal_shrink_one_cp_list() was changed to always scan a complete checkpoint list.

Source: NVD