CVE-2026-99269
Received Received - Intake

Race Condition in Linux Kernel sched_ext Component

Publication date: 2026-11-03

Last updated on: 2026-11-03

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Wait for SCX_OPSS_DISPATCHING before moving tasks off DSQs A task can be found on a non-local DSQ while the CPU which dispatched it is still running ops.dequeue() and hasn't cleared SCX_OPSS_DISPATCHING. The DSQ consume and move paths don't wait for the dispatch to finish and can operate on the task concurrently with the dispatcher. Call scx_wait_dispatching() in scx_move_local_task_to_local_dsq(), unlink_dsq_and_switch_rq_lock() and move_task_between_dsqs() before they operate on the task. In scx_move_local_task_to_local_dsq(), wait before scx_resolve_local_dsq() as it may update p->scx.flags.

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Meta Information

Published
2026-11-03
Last Modified
2026-11-03
Generated
2026-11-03
AI Q&A
2026-11-03
EPSS Evaluated
N/A
NVD
CVE-2026-99269
EUVD
EUVD-2026-115794

Affected Vendors & Products

Showing 3 associated CPEs
Vendor Product Version / Range
Linux Linux ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d
Linux Linux ebf1ccff79c43f860cbd2f9d6cfab9a462d0cb2d
Linux Linux 7.1

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Exploitability

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KEV
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CWE ID Description
CWE-UNKNOWN

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Executive Summary

This is a race condition in the Linux kernel's sched_ext subsystem. A task can appear on a non-local DSQ while the CPU dispatching it is still processing and hasn't cleared the dispatching flag. The system tries to move tasks between DSQs without waiting for the dispatch to complete, causing concurrent operations that can lead to undefined behavior or crashes.

Detection Guidance

This vulnerability is specific to the Linux kernel's sched_ext subsystem and requires kernel-level inspection. Detection involves checking kernel logs for related errors or verifying if your kernel version includes the fix. Commands like 'dmesg | grep scx' or 'uname -r' may help identify affected systems.

Impact Analysis

This vulnerability could cause system instability, crashes, or unpredictable behavior in Linux systems using the sched_ext feature. It may lead to performance degradation or unexpected task scheduling issues, potentially affecting system reliability.

Mitigation Strategies

Apply the latest kernel update from your Linux distribution to ensure the vulnerability is patched. If immediate patching is not possible, consider disabling sched_ext features if they are not critical to your operations.

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