In the Linux kernel, the following vulnerability has been resolved: ppp: require CAP_NET_ADMIN in target netns for unattached ioctls /dev/ppp open is currently authorized against file->f_cred->user_ns, while unattached administrative ioctls operate on current->nsproxy->net_ns. As a result, a local unprivileged user can create a new user namespace with CLONE_NEWUSER, gain CAP_NET_ADMIN only in that new user namespace, and still issue PPPIOCNEWUNIT, PPPIOCATTACH, or PPPIOCATTCHAN against an inherited network namespace. Require CAP_NET_ADMIN in the user namespace that owns the target network namespace before handling unattached PPP administrative ioctls. This preserves normal pppd operation in the network namespace it is actually privileged in, while rejecting the userns-only inherited-netns case.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

No data.

No data.

References
Link Providers
https://git.kernel.org/stable/c/1a8a51ce85075a56a743b6f142606dd2696a391c cve-icon
https://git.kernel.org/stable/c/2bb6379416fd19f44c3423a00bfd8626259f6067 cve-icon
https://git.kernel.org/stable/c/3b2c2157dc2afc5c17cd7238afefca92f1ef330e cve-icon
https://git.kernel.org/stable/c/5013be175c7ffd8b39efbc3c9c4db5b10b85fea8 cve-icon
https://git.kernel.org/stable/c/5080e188c914110034bbc569d5cfa2f06204681d cve-icon
https://git.kernel.org/stable/c/67e901e28d177ac9a9bed76d69ce3471e704a89e cve-icon
https://git.kernel.org/stable/c/954745d0223e7caec917c0b2d1a889ff56fa6e54 cve-icon
https://git.kernel.org/stable/c/c9edd90c57ae23692fff6b049fdfa4572a9fd532 cve-icon
https://lore.kernel.org/linux-cve-announce/2026062405-CVE-2026-53075-9f2a@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-53075 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-53075 cve-icon
History

Fri, 26 Jun 2026 04:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-284

Fri, 26 Jun 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-266
References
Metrics threat_severity

None

 cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate

Wed, 24 Jun 2026 19:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-284

Wed, 24 Jun 2026 17:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ppp: require CAP_NET_ADMIN in target netns for unattached ioctls /dev/ppp open is currently authorized against file->f_cred->user_ns, while unattached administrative ioctls operate on current->nsproxy->net_ns. As a result, a local unprivileged user can create a new user namespace with CLONE_NEWUSER, gain CAP_NET_ADMIN only in that new user namespace, and still issue PPPIOCNEWUNIT, PPPIOCATTACH, or PPPIOCATTCHAN against an inherited network namespace. Require CAP_NET_ADMIN in the user namespace that owns the target network namespace before handling unattached PPP administrative ioctls. This preserves normal pppd operation in the network namespace it is actually privileged in, while rejecting the userns-only inherited-netns case.
Title ppp: require CAP_NET_ADMIN in target netns for unattached ioctls
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2026-06-24T16:30:16.214Z

Updated: 2026-06-24T16:30:16.214Z

Reserved: 2026-06-09T07:44:35.383Z

Link: CVE-2026-53075

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-06-24T00:00:00Z

Links: CVE-2026-53075 - Bugzilla