CVE-2026-91838 Networkmanager-sstp: networkmanager-sstp: local privilege escalation to root via shell injection in vpn profile fields
Local attackers can execute arbitrary commands as root by injecting shell metacharacters into VPN profile fields processed by the pppd daemon.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-91838?
CVE-2026-91838 is a high-severity command injection vulnerability in GNOME NetworkManager-sstp, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw was found in NetworkManager-sstp, the SSTP VPN plugin for NetworkManager. A local unprivileged user can exploit this vulnerability by embedding special characters, known as shell metacharacters, into VPN connection profile fields such as CA certificate or proxy settings. These unescaped characters are then processed by the `pppd` daemon, which runs with root privileges, allowing the attacker to execute arbitrary commands with elevated permissions when a malicious VPN connection is activated.
Weakness: CWE-78
Which versions are affected by CVE-2026-91838?
How do I fix CVE-2026-91838?
No fix has been published for CVE-2026-91838 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-91838 being exploited?
There is no known exploitation of CVE-2026-91838 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-91838, GHSA-94qh-3pf4-8c4r, UBUNTU-CVE-2026-91838.