Is there a public exploit for CVE-2026-99281?

No public exploit for CVE-2026-99281 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

What does CVE-2026-99281 affect?

CVE-2026-99281 affects Linux Linux.

— Unscored

In the Linux kernel, the following vulnerability has been resolved: tun: Require CAPNETADMIN to attach to an ownerless device Twenty years…

CVE-2026-99281

In the Linux kernel, the following vulnerability has been resolved: tun: Require CAPNETADMIN to attach to an ownerless device Twenty years ago I made creating a tuntap device require CAPNETADMIN in commit ca6bb5d7ab22 ("[NET]: Require CAPNETADMIN to create tuntap devices.") The idea was to allow the permissions on /dev/net/tun to be relaxed to 0666 and thus allow owners of tun devices assigned with TUNSETOWNER to actually open it and get at their devices. What we missed at the time was that persistent devices with no owner were already essentially world-consumable, and anyone who could open the device node could also attach to those. Even then, using persistent devices with no explicitly set owner — on the (false) presumption that CAPNETADMIN would be required to open them — wasn't an egregious userspace bug. There are cases where it does make sense to separate the creation/configuration of the netdevice, from the process which shovels packets into it. Since then, TUNSETGROUP was added a year later in commit 8c644623fe7e ("[NET]: Allow group ownership of TUN/TAP devices."). Its commit message noted that if both uid and gid are set, both have to match (in itself a bizarre choice) —…

Assessment

CVSS: Not yet scored
Severity: Unscored
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 7 November 2026
Last updated: 7 November 2026
Affected: Linux · Linux
Assigner: Linux

At the source

EUVD (ENISA)

References

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