CVE-2026-43438 (GCVE-0-2026-43438)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:22 – Updated: 2026-05-11 22:24
VLAI?
Title
sched_ext: Remove redundant css_put() in scx_cgroup_init()
Summary
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.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < cc095cd305fddbe25a968e4a78436ff9476cf0f6 (git)
Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < 6eaaa67d6998f6c30c462b140db8c062e07ec473 (git)
Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < bf50f3285eda8a0173625fcdb5f183f96e1008cd (git)
Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < 1336b579f6079fb8520be03624fcd9ba443c930b (git)
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Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.19 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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