CVE-2026-91838

HIGHPre-NVD 7.87.8—
EchelonGraph scoreHIGH confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-25. A secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.1%CVSS: 7.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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.

CVSS v3
7.8
EG Score
7.8HIGHhigh confidence
EG Risk
40
EG Risk 40/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity78% × 45%
Exploitation0% × 40%
Automatability30% × 15%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.1%
EPSS %ILE
below the 1st
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 25, 2026

Last Modified

September 30, 2026

Advisory Details (3)

Auto-updated Sep 25, 2026
Patch available. Sources: redhat.
generic

(CVE-2026-91838) network-manager-sstp profile data reaches root pppd pty shell (#67) · Tickets · GNOME / network-manager-sstp · GitLab

https://gitlab.gnome.org/GNOME/network-manager-sstp/-/work_items/67
redhat

2533637 – (CVE-2026-91838) CVE-2026-91838 NetworkManager-sstp: NetworkManager-sstp: local privilege escalation to root via shell injection in VPN profile fields

https://bugzilla.redhat.com/show_bug.cgi?id=2533637
redhat Patch Available

CVE-2026-91838 - Red Hat Customer Portal

Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a

https://access.redhat.com/security/cve/CVE-2026-91838

Vendor Advisories for CVE-2026-91838(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 20× in last 7d / 30× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-10-04 00:18 UTCGHSA enrichment
  2. 2026-10-03 11:41 UTCGHSA enrichment
  3. 2026-10-02 22:32 UTCGHSA enrichment
  4. 2026-10-02 09:54 UTCGHSA enrichment
  5. 2026-10-01 21:16 UTCEG score recompute
  6. 2026-10-01 21:16 UTCGHSA enrichment
  7. 2026-10-01 19:51 UTCEPSS rescore
  8. 2026-10-01 08:38 UTCGHSA enrichment
  9. 2026-09-30 20:02 UTCEG score recompute
  10. 2026-09-30 20:02 UTCGHSA enrichment
  11. 2026-09-30 15:04 UTCEPSS rescore
  12. 2026-09-30 13:16 UTCGHSA enrichment
  13. 2026-09-30 00:39 UTCGHSA enrichment
  14. 2026-09-29 11:59 UTCGHSA enrichment
  15. 2026-09-28 23:19 UTCEG score recompute
  16. 2026-09-28 23:19 UTCGHSA enrichment
  17. 2026-09-28 10:42 UTCGHSA enrichment
  18. 2026-09-27 22:05 UTCEG score recompute
  19. 2026-09-27 22:05 UTCGHSA enrichment
  20. 2026-09-27 13:49 UTCEPSS rescore
  21. 2026-09-27 09:28 UTCGHSA enrichment
  22. 2026-09-26 20:51 UTCEG score recompute
  23. 2026-09-26 20:51 UTCGHSA enrichment
  24. 2026-09-26 15:59 UTCEPSS rescore
  25. 2026-09-26 08:13 UTCGHSA enrichment
Show 5 more
  1. 2026-09-25 19:34 UTCGHSA enrichment
  2. 2026-09-25 18:36 UTCEG score recompute
  3. 2026-09-25 18:36 UTCGHSA enrichment
  4. 2026-09-25 17:56 UTCEG score recompute
  5. 2026-09-25 17:54 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-91838?
CVE-2026-91838 is a high vulnerability published on September 25, 2026. 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…
When was CVE-2026-91838 disclosed?
CVE-2026-91838 was first published on September 25, 2026, with the most recent update on September 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-91838 actively exploited?
CVE-2026-91838 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.1% probability of exploitation in the next 30 days (below the 1st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-91838?
CVE-2026-91838 has a CVSS base score of 7.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-91838?
A fix for CVE-2026-91838 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-91838 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-91838

Explore →

Is Your Infrastructure Affected by CVE-2026-91838?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs