CVE-2026-43438

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1336b579f6079fb8520be03624fcd9ba443c930b	Patch
https://git.kernel.org/stable/c/6eaaa67d6998f6c30c462b140db8c062e07ec473	Patch
https://git.kernel.org/stable/c/bf50f3285eda8a0173625fcdb5f183f96e1008cd	Patch
https://git.kernel.org/stable/c/cc095cd305fddbe25a968e4a78436ff9476cf0f6	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43438

Mitre link : CVE-2026-43438

CVE.ORG link : CVE-2026-43438

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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