UBUNTU-CVE-2026-31575

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 24 Apr 2026, 15:16
Last modified:04 Jun 2026, 17:59

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

24 Apr 2026, 15:16
Published
Vulnerability first disclosed
04 Jun 2026, 17:59
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: mm/userfaultfd: fix hugetlb fault mutex hash calculation In mfill_atomic_hugetlb(), linear_page_index() is used to calculate the page index for hugetlb_fault_mutex_hash(). However, linear_page_index() returns the index in PAGE_SIZE units, while hugetlb_fault_mutex_hash() expects the index in huge page units. This mismatch means that different addresses within the same huge page can produce different hash values, leading to the use of different mutexes for the same huge page. This can cause races between faulting threads, which can corrupt the reservation map and trigger the BUG_ON in resv_map_release(). Fix this by introducing hugetlb_linear_page_index(), which returns the page index in huge page granularity, and using it in place of linear_page_index().

CVSS Metrics

  • v3.1MEDIUMScore: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Systems

  • ubuntulinux

    all | all | all | all | all

  • ubuntulinux-allwinner-5.19

    all

  • ubuntulinux-aws

    all | all | all | all | all

  • ubuntulinux-aws-5.0

    all

  • ubuntulinux-aws-5.11

    all

  • ubuntulinux-aws-5.13

    all

  • ubuntulinux-aws-5.15

    all

  • ubuntulinux-aws-5.19

    all

  • ubuntulinux-aws-5.3

    all

  • ubuntulinux-aws-5.4

    all

  • ubuntulinux-aws-5.8

    all

  • ubuntulinux-aws-6.14

    all

  • ubuntulinux-aws-6.17

    all

  • ubuntulinux-aws-6.2

    all

  • ubuntulinux-aws-6.5

    all

  • ubuntulinux-aws-6.8

    all

  • ubuntulinux-aws-fips

    all

  • ubuntulinux-aws-hwe

    all

  • ubuntulinux-azure

    all | all | all | all | all | all

  • ubuntulinux-azure-4.15

    all

  • ubuntulinux-azure-5.11

    all

  • ubuntulinux-azure-5.13

    all

  • ubuntulinux-azure-5.15

    all

  • ubuntulinux-azure-5.19

    all

  • ubuntulinux-azure-5.3

    all

  • ubuntulinux-azure-5.4

    all

  • ubuntulinux-azure-5.8

    all

  • ubuntulinux-azure-6.11

    all

  • ubuntulinux-azure-6.14

    all

  • ubuntulinux-azure-6.17

    all

  • ubuntulinux-azure-6.2

    all

  • ubuntulinux-azure-6.5

    all

  • ubuntulinux-azure-6.8

    all

  • ubuntulinux-azure-edge

    all

  • ubuntulinux-azure-fde

    all | all | all | all | all

  • ubuntulinux-azure-fde-5.15

    all

  • ubuntulinux-azure-fde-5.19

    all

  • ubuntulinux-azure-fde-6.14

    all

  • ubuntulinux-azure-fde-6.17

    all

  • ubuntulinux-azure-fde-6.2

    all

  • ubuntulinux-azure-fde-6.8

    all

  • ubuntulinux-azure-fips

    all

  • ubuntulinux-azure-nvidia

    all

  • ubuntulinux-azure-nvidia-6.14

    all

  • ubuntulinux-bluefield

    all | all

  • ubuntulinux-fips

    all

  • ubuntulinux-gcp

    all | all | all | all | all | all

  • ubuntulinux-gcp-4.15

    all

  • ubuntulinux-gcp-5.11

    all

  • ubuntulinux-gcp-5.13

    all

Showing first 50 affected entries in server-rendered view.

References (3)