CVE intelligence

CVE-2026-98079

Vulnerability intelligence

Published Sep 25, 2026Sources checked Nov 12, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-98079. 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 7, 2026

Release Notes

Vendor-listed releases

6.6.161.1-1

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-2026-98079?

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

btrfs: zstd: fix lost wakeup when waiting for a workspace

A writer can sleep forever in zstd_get_workspace() even though a workspace is free.

When zstd_alloc_workspace() fails, the task is queued on zwsm->wait and schedules unconditionally, never re-testing the pool. zstd_put_workspace() publishes the workspace and then calls cond_wake_up(), which only wakes when a sleeper is already visible, so a workspace returned between the failed allocation and prepare_to_wait() wakes nobody.

The window is wide: zstd_alloc_workspace() goes through kvmalloc() and may enter reclaim.

Only a max level workspace triggers the wakeup and one is deliberately kept allocated as the fallback every waiter waits for, so once its wakeup is lost the writer stays in TASK_UNINTERRUPTIBLE until some other task happens to return one. Re-check the pool after prepare_to_wait() has published the waiter, and use the workspace if one turned up.

Source: NVD