futex: Avoid private hash use-after-free on final put

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-80758
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-09-04 16:18:00 UTC
Updated2026-09-04 16:18:00 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: futex: Avoid private hash use-after-free on final put futex_private_hash_put() drops the reference to fph before evaluating fph->mm for wake_up_var(). futex_ref_put() enables preemption again before returning. If that put drops the final reference and the task is preempted, another task can pivot to the replacement hash and free the old hash after an RCU grace period. The first task then reads fph->mm from the freed allocation when it resumes. KASAN reports a slab-use-after-free in futex_private_hash_put(), with the read at offset 24 in a freed kmalloc-512 allocation. The allocation and free stacks point to futex_hash_allocate() and the RCU free path, respectively. Load the mm pointer while the fph reference is still held and pass the saved value to wake_up_var(). wake_up_var() uses the pointer as a waitqueue key and does not dereference the mm through it.

Risk And Classification

EPSS: 0.001680000 probability, percentile 0.063070000 (date 2026-09-07)

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected bd54df5ea7cadac520e346d5f0fe5d58e635b6ba dba60d26e9dda3e157ad6b0934d4232f6c6904ee git Not specified
CNA Linux Linux affected bd54df5ea7cadac520e346d5f0fe5d58e635b6ba 12cd315a7b6a7d7db3f69d98bfe3909275e9451d git Not specified
CNA Linux Linux affected bd54df5ea7cadac520e346d5f0fe5d58e635b6ba 25408c62ed4ebcd491d0e9e4b4a5b512547512e4 git Not specified
CNA Linux Linux affected bd54df5ea7cadac520e346d5f0fe5d58e635b6ba 1c7efabfbaf796f11000a46094a69955a01ec6cc git Not specified
CNA Linux Linux affected 6.16 Not specified
CNA Linux Linux unaffected 6.16 semver Not specified
CNA Linux Linux unaffected 6.18.47 6.18.* semver Not specified
CNA Linux Linux unaffected 7.1.11 7.1.* semver Not specified
CNA Linux Linux unaffected 7.2.1 7.2.* semver Not specified
CNA Linux Linux unaffected 7.3-rc1 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/1c7efabfbaf796f11000a46094a69955a01ec6cc 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/dba60d26e9dda3e157ad6b0934d4232f6c6904ee 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/12cd315a7b6a7d7db3f69d98bfe3909275e9451d 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/25408c62ed4ebcd491d0e9e4b4a5b512547512e4 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report