Answer in brief
CVE-2026-74731 records a High severity (CVSS 7.8) vulnerability in sched_ext: Skip sub-disable teardown for never-linked sub-schedulers. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=337ec00b1d9c676f637651c2cefddb8612b867ee <6428093a4a986c38c9089b5eb32b56d914ef437a || >=337ec00b1d9c676f637651c2cefddb8612b867ee <8c13364db9c9a43ed286f3a8d0fb9477b1adc43c | 6428093a4a986c38c9089b5eb32b56d914ef437a, 8c13364db9c9a43ed286f3a8d0fb9477b1adc43c |
| Linux/Linuxgeneric | 7.1 | Not reported |
Published upstream
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 22, 2026
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.
Quoted source text, attributed separately from HOL analysis.