What is CVE-2026-91840?

CVE-2026-91840 is a high-severity vulnerability in GNOME Networkmanager-Vpnc, classified under CRLF Injection. CVSS score: 7.8/10. Published 2026-09-25.

How severe is CVE-2026-91840?

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

Vulnerability in GNOME Networkmanager-Vpnc

CVE-2026-91840

A flaw was found in NetworkManager-vpnc. This vulnerability allows a local unprivileged user to escalate privileges to root. By injecting a newline character into the VPN username field, an attacker can manipulate the vpnc configuration to execute an arbitrary program with root privileges when the malicious 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-Vpnc

Weakness classification (CWE)

CWE-93 — CRLF Injection

References

access.redhat.com/security/cve/CVE-2026-91840 (vdb-entry)
bugzilla.redhat.com/show_bug.cgi (issue-tracking)
gitlab.gnome.org/Archive/NetworkManager-vpnc/-/work_items/19

Frequently asked questions

What is CVE-2026-91840?: CVE-2026-91840 is a high-severity vulnerability in GNOME Networkmanager-Vpnc, classified under CRLF Injection. CVSS score: 7.8/10. Published 2026-09-25.
How severe is CVE-2026-91840?: High severity. CVSS v3 base score is 7.8 out of 10.