UBUNTU-CVE-2026-31694

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 01 May 2026, 14:16
Last modified:04 Jun 2026, 17:59

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

01 May 2026, 14:16
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: fuse: reject oversized dirents in page cache fuse_add_dirent_to_cache() computes a serialized dirent size from the server-controlled namelen field and copies the dirent into a single page-cache page. The existing logic only checks whether the dirent fits in the remaining space of the current page and advances to a fresh page if not. It never checks whether the dirent itself exceeds PAGE_SIZE. As a result, a malicious FUSE server can return a dirent with namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB page systems this causes memcpy() to overflow the cache page by 24 bytes into the following kernel page. Reject dirents that cannot fit in a single page before copying them into the readdir cache.

CVSS Metrics

  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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)