Improper access control in Linux kernel - CVE-2026-72379

CSH
CYBERSECURITY HELP
Sign In REGISTER
 
Main Vulnerability Database Vulnerabilities #VU143060

Improper access control in Linux kernel - CVE-2026-72379

Published: August 15, 2026


Vulnerability identifier: #VU143060
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-72379
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to create a temporary file with invalid ownership.

The vulnerability exists due to improper access control in vfs_tmpfile() when creating an O_TMPFILE on an idmapped mount that does not map the caller's fsuid or fsgid. A local user can create a temporary file on such a mount to create a temporary file with invalid ownership.

The issue affects filesystems that support idmapped mounts and implement tmpfile handling, as well as overlayfs through upper-layer tmpfile creation.


Affected software

Linux kernel
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)

How to mitigate CVE-2026-72379

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1

External References

Related Security Bulletins