AEGLIX vulnerability intelligence
CVE-2026-99085
UNSCORED · Received
Published: 2026-10-23 · Updated: 2026-10-23 · Source: NVD
Stored catalog record
Source record retrieved 2026-10-28T10:21:00.308149+00:00. Scheduled imports handle updates; this page does not assert that the provider was queried just now.
Vulnerability overview
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix CPU hotplug hang when a dying CPU's tasks sit in the BPF scheduler A CPU going down has to empty its own rq. Its hotplug thread waits in sched_cpu_wait_empty() until nothing else is left, and the only thing that wakes it is balance_push(), which runs from __schedule() on the dying CPU and pushes off the migratable tasks the CPU picks. sched_ext breaks this. A task sitting on a user DSQ or held by the BPF scheduler is still counted on its rq, but an inactive CPU no longer calls ops.dispatch() and can't pull the task back. The dying CPU goes idle with the task still counted, and one of two things happens: - Another CPU consumes the task. The rq empties without a __schedule() on the dying CPU, so the hotplug thread is never woken and cpu_down() hangs holding cpu_hotplug_lock. - The task is affine only to the dying CPU. Nothing can move it, and the offline stalls until the watchdog ejects the BPF scheduler. When the rq goes offline, re-enqueue every task on it that isn't already on the local DSQ. An enqueue on an offline rq lands on the local DSQ, so the dying CPU itself picks the tasks and balance_push() pushes them off, the same as for the other sched classes. From then on no sched_ext path on another CPU can pull a task off the rq. ops.dispatch() currently stops as soon as the CPU goes inactive, and CPU hotplug then waits for an RCU grace period before taking the rq offline. A BPF-held task affine only to the dying CPU and preempted inside an RCU read-side critical section would block that grace period, and the rq would never go offline. Test SCX_RQ_ONLINE directly so that ops.dispatch() keeps running until the rq goes offline. Only the dying CPU's own hotplug thread clears the flag during teardown, and task_can_run_on_remote_rq() still keeps other rqs' tasks off the CPU.
Patch review priority
Assess exposure and vendor guidance
- No higher-priority signal is available in the current stored evidence.
FIRST EPSS: 0.16% · percentile 5.6 · score date 2026-10-27.
EPSS estimates probability of exploitation in the next 30 days. It does not measure your exposure or prove exploitation. The elevated threshold is 10%; CISA KEV takes precedence. About FIRST EPSS ↗
Severity and scoring
- CVSS score
- Not scored · UNSCORED
- CVSS version
- Not supplied
- CVSS vector
- Not supplied
- Weaknesses
- Not supplied
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Not listed in the CISA catalog retrieved for this record. This does not establish that exploitation has not occurred.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
NVD has not supplied affected-version configurations for this record. Check the vendor references below.