---
id: CVE-2026-91838
title: >-
  A flaw was found in NetworkManager-sstp, the SSTP VPN plugin for
  NetworkManager
summary: >-
  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 …
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-78
vendor: GNOME
product: network-manager-sstp
affected:
  - network-manager-sstp < *
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T19:17:58.647'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91838'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-91838'
    label: patrick@puiterwijk.org
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2533637'
    label: patrick@puiterwijk.org
  - url: 'https://gitlab.gnome.org/GNOME/network-manager-sstp/-/work_items/67'
    label: patrick@puiterwijk.org
  - url: 'https://gitlab.gnome.org/GNOME/network-manager-sstp/-/work_items/67'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91838.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-91838'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-25T18:16:05.405073Z'
ingestedAt: '2026-09-25T18:14:20.402Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · updated 2026-09-25 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91838.json)