In the Linux kernel, the following vulnerability has been resolved: sched_ext: Read scx_root under scx_cgroup_ops_rwsem in cgroup setters scx_group_set_{weight,idle,bandwidth}() cache scx_root before acquiring scx_cgroup_ops_rwsem, so the pointer can be stale by the time the op runs. If the loaded scheduler is disabled and freed (via RCU work) and another is enabled between the naked load and the rwsem acquire, the reader sees scx_cgroup_enabled=true (the new scheduler's) but dereferences the freed one - UAF on SCX_HAS_OP(sch, ...) / SCX_CALL_OP(sch, ...). scx_cgroup_enabled is toggled only under scx_cgroup_ops_rwsem write (scx_cgroup_{init,exit}), so reading scx_root inside the rwsem read section correlates @sch with the enabled snapshot.

A flaw was found in the Linux kernel, specifically within the `sched_ext` component. This vulnerability, a use-after-free, occurs in the cgroup setters when the `scx_root` pointer is cached before a required lock is acquired. This can lead to a stale pointer if a scheduler is disabled and then re-enabled, allowing a local attacker to potentially cause a denial of service or achieve privilege escalation.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-46154 https://nvd.nist.gov/vuln/detail/CVE-2026-46154 https://lore.kernel.org/linux-cve-announce/2026052823-CVE-2026-46154-3357@gregkh/T