Task stalls via missed scheduler class changes
Published Oct 28, 2026 · Updated Oct 28, 2026
Linux 7.0 scheduler races allow context-dependent attackers to stall runnable tasks via concurrent scheduling-class changes. In kernel/sched/core.c, sched_change_end() skips preemption reevaluation for queued, non-running tasks, leaving rq->next_class stale and allowing the CPU to idle despite runnable work. The race requires task promotion during new-idle balancing; attacker control and required privileges are undocumented.
Summary
What happened
Linux 7.0 scheduler races allow context-dependent attackers to stall runnable tasks via concurrent scheduling-class changes. In kernel/sched/core.c, sched_change_end() skips preemption reevaluation for queued, non-running tasks, leaving rq->next_class stale and allowing the CPU to idle despite runnable work. The race requires task promotion during new-idle balancing; attacker control and required privileges are undocumented.
The record
- CVE
- CVE-2026-99205
- Published
- Oct 28, 2026
- Updated
- Oct 28, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 28, 2026CVE publishedPublication date reported by the CVE source.
- Oct 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=7.0
- Affected versionversion=704069649b5bfb7bf1fe32c0281fe9036806a59a <118a2cf4ced60777a2408001e2b4838fed1cea55
- Affected versionversion=704069649b5bfb7bf1fe32c0281fe9036806a59a <ae89744c5ebf299bf55ac7581768fbd9f119a903
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
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Public exploit references
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Technologies
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