Expired Pointer Dereference Affecting kernel6.18-modules-extra-common package, versions <1:6.18.56-125.164.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.2% (9th percentile)

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  • Snyk IDSNYK-AMZN2023-KERNEL618MODULESEXTRACOMMON-21804224
  • published29 Oct 2026
  • disclosed18 Oct 2026

Introduced: 18 Oct 2026

NewCVE-2026-98463  (opens in a new tab)
CWE-825  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 kernel6.18-modules-extra-common to version 1:6.18.56-125.164.amzn2023 or higher.
This issue was patched in ALAS2023-2026-3251.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel6.18-modules-extra-common package and not the kernel6.18-modules-extra-common package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

sched_ext: Derive SCX_RQ_IN_WAKEUP from the core enqueue flags

schedule_deferred_locked() skips scheduling a deferred action while SCX_RQ_IN_WAKEUP is set and relies on the task_woken_scx() call that follows a wakeup enqueue to run it. enqueue_task_scx() sets the flag from the merged enqueue flags, which include the flags stashed for a remote activation. move_remote_task_to_local_dsq() thus sets SCX_RQ_IN_WAKEUP on the destination rq when the moved task was woken up, although no task_woken_scx() follows that activation.

An IMMED insert into a busy destination requests a local reenqueue during that enqueue. The request gets linked but not scheduled and stays pending until an unrelated wakeup or preemption on that CPU runs the deferred actions. The IMMED task sits behind the running task in the meantime. If nothing runs them before the scheduler is disabled, the request outlives the scheduler and points into its freed per-cpu area, which the next scheduler dereferences from run_deferred().

Test the core enqueue flags for the wakeup bit. Only the core's wakeup path is followed by task_woken_scx().

CVSS Base Scores

version 3.1