Vulnerability-Lookup

FKIE_CVE-2026-31481

Vulnerability from fkie_nvd - Published: 2026-04-22 14:16 - Updated: 2026-04-28 11:38

Severity ?

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

Summary

In the Linux kernel, the following vulnerability has been resolved: tracing: Drain deferred trigger frees if kthread creation fails Boot-time trigger registration can fail before the trigger-data cleanup kthread exists. Deferring those frees until late init is fine, but the post-boot fallback must still drain the deferred list if kthread creation never succeeds. Otherwise, boot-deferred nodes can accumulate on trigger_data_free_list, later frees fall back to synchronously freeing only the current object, and the older queued entries are leaked forever. To trigger this, add the following to the kernel command line: trace_event=sched_switch trace_trigger=sched_switch.traceon,sched_switch.traceon The second traceon trigger will fail and be freed. This triggers a NULL pointer dereference and crashes the kernel. Keep the deferred boot-time behavior, but when kthread creation fails, drain the whole queued list synchronously. Do the same in the late-init drain path so queued entries are not stranded there either.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/250ab25391edeeab8462b68be42e4904506c409c	Patch
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/771624b7884a83bb9f922ae64ee41a5f8b7576c9	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	6.19
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

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CVE-2026-31481 (GCVE-0-2026-31481)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-05-11 22:09

Title

tracing: Drain deferred trigger frees if kthread creation fails

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

2 references

URL	Tags
https://git.kernel.org/stable/c/771624b7884a83bb9…
https://git.kernel.org/stable/c/250ab25391edeeab8…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 61d445af0a7c70018111919e47beaaee15653f2f , < 771624b7884a83bb9f922ae64ee41a5f8b7576c9 (git) Affected: 61d445af0a7c70018111919e47beaaee15653f2f , < 250ab25391edeeab8462b68be42e4904506c409c (git)
Linux	Linux	Affected: 6.19 Unaffected: 0 , < 6.19 (semver) Unaffected: 6.19.11 , ≤ 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.

Action not permitted

FKIE_CVE-2026-31481

CVE-2026-31481 (GCVE-0-2026-31481)

Tags

Sightings

Nomenclature