CVE-2026-43438
Description
In the Linux kernel, the following vulnerability has been resolved: sched_ext: Remove redundant css_put() in scx_cgroup_init() The iterator css_for_each_descendant_pre() walks the cgroup hierarchy under cgroup_lock(). It does not increment the reference counts on yielded css structs. According to the cgroup documentation, css_put() should only be used to release a reference obtained via css_get() or css_tryget_online(). Since the iterator does not use either of these to acquire a reference, calling css_put() in the error path of scx_cgroup_init() causes a refcount underflow. Remove the unbalanced css_put() to prevent a potential Use-After-Free (UAF) vulnerability.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Linux kernel Affected 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 7.0 | Affected | — |
| — | Affected | 6.12.78 |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.85-1 |
| sid | Fixed | 6.19.10-1 |
| forky | Fixed | 6.19.10-1 |
| bullseye | Fixed | 0 |
| bookworm | Fixed | 0 |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| gcp | | |
References
- https://git.kernel.org/stable/c/1336b579f6079fb8520be03624fcd9ba443c930b
- https://git.kernel.org/stable/c/6eaaa67d6998f6c30c462b140db8c062e07ec473
- https://git.kernel.org/stable/c/bf50f3285eda8a0173625fcdb5f183f96e1008cd
- https://git.kernel.org/stable/c/cc095cd305fddbe25a968e4a78436ff9476cf0f6
- https://www.suse.com/security/cve/CVE-2026-43438.html
- https://security-tracker.debian.org/tracker/CVE-2026-43438
CWEs
CWE-416
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.