What is CVE-2026-91839?

CVE-2026-91839 is a high-severity vulnerability in GNOME Networkmanager-Fortisslvpn, classified under CRLF Injection. CVSS score: 7.8/10. Published 2026-09-25.

How severe is CVE-2026-91839?

High severity. CVSS v3 base score is 7.8 out of 10.

Vulnerability in GNOME Networkmanager-Fortisslvpn

CVE-2026-91839

A flaw was found in NetworkManager-fortisslvpn, the FortiSSLVPN plugin for NetworkManager. The nm-fortisslvpn-service improperly handles carriage-return/line-feed (CR/LF) characters in VPN connection profile credentials. A local unprivileged user can exploit this by crafting a malicious VPN profile to inject additional configuration directives. This can lead to arbitrary code execution with root privileges when the crafted VPN connection is activated.

Vulnerability class: CRLF Injection

Published 2026-09-25 · last modified 2026-09-26.

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

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

GNOME Networkmanager-Fortisslvpn

Weakness classification (CWE)

CWE-93 — CRLF Injection

References

access.redhat.com/security/cve/CVE-2026-91839 (vdb-entry)
bugzilla.redhat.com/show_bug.cgi (issue-tracking)
gitlab.gnome.org/Archive/NetworkManager-fortisslvpn/-/work_items/80

Frequently asked questions

What is CVE-2026-91839?: CVE-2026-91839 is a high-severity vulnerability in GNOME Networkmanager-Fortisslvpn, classified under CRLF Injection. CVSS score: 7.8/10. Published 2026-09-25.
How severe is CVE-2026-91839?: High severity. CVSS v3 base score is 7.8 out of 10.