OS Command Injection in NetworkManager-sstp (CVE-2026-91838)
Summary
OS command injection in NetworkManager-sstp (CVE-2026-91838). Successful exploitation can lead to full system takeover. Exploitable via pppd.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-91838 has been found in NetworkManager-sstp.
Attackers can target a specific entry point like pppd over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "NetworkManager-sstp CVE-2026-91838" on the vendor's site.
CVE-2026-91838 (NetworkManager-sstp) — CWE-78 / CVSS v3 7.8
Attack vector: local / no user interaction
Attack surface: pppd
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
OS command injection (CWE-78) exists in NetworkManager-sstp. Attackers reach the vulnerable code path via pppd.
Check the vendor advisory for the affected versions of NetworkManager-sstp. Attack surface: pppd.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'NetworkManager-sstp' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'NetworkManager-sstp' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
NetworkManager-sstpを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-91838 network-manager-sstp
- Ubuntu UBUNTU-CVE-2026-91838 network-manager-sstp
References
- web access.redhat.com
- web bugzilla.redhat.com
- web gitlab.gnome.org
- web nvd.nist.gov
- web github.com