# CVE-2026-99269: Linux kernel sched_ext race condition in task dispatch handling

Source: https://junglewise.ai/threats/cve-2026-99269-in-the-linux-kernel-the-following-vulnerability-has-been-resolved  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-03. Updated: 2026-11-03  
License: CC BY 4.0 with a link back

CVE-2026-99269 · Severity: info · Published 2026-11-03

The Linux kernel's task scheduler extension (sched_ext) contains a race condition where tasks can be moved or consumed from dispatch queues while a CPU is still updating the task's state during dequeue operations. This could allow concurrent access to task state, potentially causing scheduler instability, data corruption, or system hangs.

Technologies: [Linux Kernel](https://junglewise.ai/threats/technologies/kernel). Vendors: [Linux](https://junglewise.ai/threats/vendors/linux).

## Quick answers

**Is CVE-2026-99269 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-99269 being exploited in the wild.

**How severe is CVE-2026-99269?** Informational severity, published 3 November 2026.

**Which products and versions are affected?** Linux Kernel v7.1 and later (sched_ext functionality added in v7.1).

**Is there a fix for CVE-2026-99269?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-99269 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-99269?** Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a race condition in sched_ext's task dispatch mechanism: a task can be found on a non-local dispatch queue (DSQ) while the dispatching CPU is still executing ops.dequeue() without having cleared the SCX_OPSS_DISPATCHING flag. The DSQ consume and move paths do not wait for dispatch completion, allowing concurrent access to task state. The fix adds scx_wait_dispatching() calls in three functions (scx_move_local_task_to_local_dsq, unlink_dsq_and_switch_rq_lock, and move_task_between_dsqs) to synchronize with ongoing dispatch operations.

## Affected products

- Linux Linux kernel v7.1 and later (sched_ext functionality added in v7.1)

## Timeline

- 2026-11-03: disclosed

## References

- [https://git.kernel.org/stable/c/2935062be77113c1c4565ca9d0c72180449aafee](https://git.kernel.org/stable/c/2935062be77113c1c4565ca9d0c72180449aafee)
- [https://git.kernel.org/stable/c/cc2839946328c1618b3870d521b32bb9483d49d0](https://git.kernel.org/stable/c/cc2839946328c1618b3870d521b32bb9483d49d0)

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