Quick answers
- Is CVE-2026-91840 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-91840 being exploited in the wild.
- How severe is CVE-2026-91840?
- High severity, with a CVSS score of 7.8, published 25 September 2026.
- Which products and versions are affected?
- GNOME NetworkManager-vpnc.
- Is there a fix for CVE-2026-91840?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-91840 attacked?
- It is attacked with local access.
- Am I affected by CVE-2026-91840?
- Check whether you run Gnome NetworkManager-vpnc. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a CRLF injection flaw (CWE-93) in the VPN username field that allows an attacker to inject configuration directives into the vpnc configuration file. An unprivileged local user can craft a malicious VPN profile with a specially crafted username containing newline characters; when the connection is activated, vpnc executes arbitrary commands with root privileges. Exploitation requires local access and user interaction to activate the VPN connection, but results in complete privilege escalation to root.
Affected products
- GNOME NetworkManager-vpnc
Timeline
- 2026-09-25: disclosed