In the Linux kernel, the following vulnerability has been resolved: sched_ext: Read scx_root...

CVE-2026-46154 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

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.

Basic information

Type
unreviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
—
Source code
Not specified
Published (advisory)
2026-05-28 12:30:31 UTC
Updated
2026-06-09 21:32:19 UTC
NVD published
2026-05-28

EPSS Score

Score Percentile
0.01% 2.25%

CVSS Scores

Base score Version Severity Vector
7.0 3.1 —
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-xcff-q6mv-v46w ↗
CVE CVE-2026-46154 ↗

CWEs

CWE id Name
CWE-416 Use After Free

References

cvelogic Threat Intelligence