Quick answers
- Is CVE-2026-99281 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-99281 being exploited in the wild.
- How severe is CVE-2026-99281?
- Informational severity, published 7 November 2026.
- Which products and versions are affected?
- Linux Kernel prior to fix (2026-11-07).
- Is there a fix for CVE-2026-99281?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-99281 attacked?
- It is attacked with local access, in an operating system.
- Am I affected by CVE-2026-99281?
- Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The TUN/TAP device driver had a privilege escalation flaw where persistent devices without an explicit owner or group assignment could be attached to by any user who could open /dev/net/tun, despite prior fixes attempting to enforce CAP_NET_ADMIN checks. The vulnerability stems from a 2024 attempted fix that was reverted due to a false compatibility concern with SELinux test expectations. The fix now properly enforces that attachment to an ownerless device requires either matching user/group ownership or CAP_NET_ADMIN capability.
Affected products
- Linux Linux kernel prior to fix (2026-11-07)
Timeline
- 2026-11-07: advisory