CVE-2026-23111: nf_tables bug grants local root and container breakout

Colleagues — alert: a working exploit for CVE-2026-23111 (nf_tables use-after-free) is public, enabling local privilege escalation to root and container escape.

Summary:
- Cause: inverted check in nf_tables; upstream fix released 5 Feb 2026.
- Public exploits: FuzzingLabs (April), Exodus (8 June).
- Trigger: nf_tables combined with unprivileged user namespaces; no remote vector.
- Risk: compromised container/service can obtain host root.

Action: update the kernel, reboot, and, where possible, restrict unprivileged user namespaces.

How will you respond to this LPE wave?

#cybersecurity #Linux #vulnerabilities #containers