Vulnerability-Lookup

FKIE_CVE-2026-43438

Vulnerability from fkie_nvd - Published: 2026-05-08 15:16 - Updated: 2026-05-21 17:28

Severity ?

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1336b579f6079fb8520be03624fcd9ba443c930b	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6eaaa67d6998f6c30c462b140db8c062e07ec473	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/bf50f3285eda8a0173625fcdb5f183f96e1008cd	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/cc095cd305fddbe25a968e4a78436ff9476cf0f6	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

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

Vulnerability from cvelistv5 – Published: 2026-05-08 14:22 – Updated: 2026-05-11 22:24

Title

sched_ext: Remove redundant css_put() in scx_cgroup_init()

Summary

Severity ?

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux

References

4 references

URL	Tags
https://git.kernel.org/stable/c/cc095cd305fddbe25…
https://git.kernel.org/stable/c/6eaaa67d6998f6c30…
https://git.kernel.org/stable/c/bf50f3285eda8a017…
https://git.kernel.org/stable/c/1336b579f6079fb85…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < cc095cd305fddbe25a968e4a78436ff9476cf0f6 (git) Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < 6eaaa67d6998f6c30c462b140db8c062e07ec473 (git) Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < bf50f3285eda8a0173625fcdb5f183f96e1008cd (git) Affected: 8195136669661fdfe54e9a8923c33b31c92fc1da , < 1336b579f6079fb8520be03624fcd9ba443c930b (git)
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)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

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.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

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FKIE_CVE-2026-43438

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

Tags

Sightings

Nomenclature