Improper access control in Linux kernel - CVE-2026-53075

 

Improper access control in Linux kernel - CVE-2026-53075

Published: June 25, 2026


Vulnerability identifier: #VU135244
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-53075
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability: No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel

Detailed vulnerability description

The vulnerability allows a local user to perform unauthorized PPP administrative operations in an inherited network namespace.

The vulnerability exists due to improper access control in unattached PPP administrative ioctl handling in drivers/net/ppp/ppp_generic.c when processing PPPIOCNEWUNIT, PPPIOCATTACH, or PPPIOCATTCHAN requests. A local user can create a new user namespace and issue crafted ioctl requests to perform unauthorized PPP administrative operations in an inherited network namespace.

Exploitation requires the ability to create a new user namespace with CLONE_NEWUSER.


How to mitigate CVE-2026-53075

Install security update from vendor's repository.

Sources