RCE in GNOME Networkmanager-Sstp
CVE-2026-91838
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.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.001 (0.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 0.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-91838 (vdb-entry)
- RHBZ#2533637 (issue-tracking)
- gitlab.gnome.org/GNOME/network-manager-sstp/-/work_items/67
Frequently asked questions
- What is CVE-2026-91838?
- CVE-2026-91838 is a high-severity vulnerability in GNOME Networkmanager-Sstp, classified under OS Command Injection. CVSS score: 7.8/10. Published 2026-09-25.
- How severe is CVE-2026-91838?
- High severity. CVSS v3 base score is 7.8 out of 10.