CVE-2026-19624

Description

A flaw was found in NetworkManager-l2tp. The plugin writes attacker-controlled VPN connection properties (vpn.data and vpn.secrets values) unescaped into a generated ipsec.conf file that pluto loads as root. A local unprivileged user can create and activate their own L2TP VPN profile containing a newline-injected leftupdown directive; pluto executes that command as root when the IKE security association is established, resulting in local privilege escalation. This is the same bug class as CVE-2018-10900 (NetworkManager-vpnc).

References

• https://bodhi.fedoraproject.org/updates/?packages=NetworkManager-l2tp
• https://github.com/nm-l2tp/NetworkManager-l2tp/commit/3704d8c9d5e5f9ed1626a8ce7627a04247cea673
• https://github.com/nm-l2tp/NetworkManager-l2tp/commit/95b6b46f48a0c9eabc79272cd313f219110ef91c
• https://github.com/nm-l2tp/NetworkManager-l2tp/releases
• https://linnemanlabs.com/posts/nm-l2tp-newline-to-root/