# CVE-2026-74731 — Linux

> As of 2026-08-22, CVE-2026-74731 is a vulnerability in Linux, EPSS 0.1% (9.8th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-74731 as of 2026-08-22; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-08-22

## What is CVE-2026-74731?

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Skip sub-disable teardown for never-linked sub-schedulers A sub-scheduler enable can fail before scx_link_sched() links the sched into the hierarchy, e.g. when the parent is already being disabled, and cleanup still runs the full scx_sub_disable(). That is racy against root disable: drain_descendants() is the only ordering between a sub's disable-time task walk and root disable's all-task teardown, and an unlinked sub is invisible to it. Root's teardown can thus run between the never-linked sub's drain and its walk, exiting every task to no scheduler. The walk then trips the membership WARN and re-homes the exited tasks onto the dying hierarchy, a use-after-free. Skip the cgroup ownership reset and the task walk if @sch was never linked, indicated by the empty ->sibling as unlinking only happens later in the same function. The membership WARN remains valid: a linked sub is always waited on by an ancestor's drain.

1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 44 days ago.

## Severity and exploitation probability

- **EPSS (FIRST):** 0.1% probability of exploitation in the next 30 days, higher than 9.8% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 0.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-22

## Is CVE-2026-74731 being exploited?

It currently carries a trending score of 32 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Linux](https://intel.threadlinqs.com/vendors/linux): Linux

## How to fix CVE-2026-74731

No vendor patch reference has been recorded for CVE-2026-74731 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-74731

No threat campaign in the Threadlinqs corpus currently references CVE-2026-74731, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-08-23.

**Other references**

- [git.kernel.org](https://git.kernel.org/stable/c/6428093a4a986c38c9089b5eb32b56d914ef437a)
- [git.kernel.org (8c13364db9c9a43ed286f3a8d0fb9477b1adc43c)](https://git.kernel.org/stable/c/8c13364db9c9a43ed286f3a8d0fb9477b1adc43c)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-74731
Full detection coverage and IOCs for threats exploiting CVE-2026-74731 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp