ppp: require CAP_NET_ADMIN in target netns for unattached ioctls (Linux Linux)

CVE-2026-53075
HIGH 8.8

At a glance

Source
NVD
EPSS
EPSS 0.27 % · percentile 20 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

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.

Weaknesses (CWE)

  • CWE-863 — Incorrect Authorization

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HLinux
CVSS 3.1HIGH 8.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 273ec51dd7ceaa76e038875d85061ec856d8905e < c9edd90c57ae23692fff6b049fdfa4572a9fd532 ; affected 273ec51dd7ceaa76e038875d85061ec856d8905e < 5080e188c914110034bbc569d5cfa2f06204681d ; affected 273ec51dd7ceaa76e038875d85061ec856d8905e < 67e901e28d177ac9a9bed76d69ce3471e704a89e ; affected 273ec51dd7ceaa76e038875d85061ec856d8905e < 954745d0223e7caec917c0b2d1a889ff56fa6e54 ; affected 273ec51dd7ceaa76e038875d85061ec856d8905e < 3b2c2157dc2afc5c17cd7238afefca92f1ef330e ; affected 273ec51dd7ceaa76e038875d85061ec856d8905e < 5013be175c7ffd8b39efbc3c9c4db5b10b85fea8
Linux · Linuxaffected 2.6.30 ; unaffected 0 < 2.6.30 ; unaffected 5.10.258 ≤ 5.10.* ; unaffected 5.15.209 ≤ 5.15.* ; unaffected 6.1.175 ≤ 6.1.* ; unaffected 6.6.141 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD