CVE-2026-91840 (CVSS 7.8)

Description

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.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0019

Probability of exploitation

0.09%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-93 CWE-93

References

Other References

https://access.redhat.com/security/cve/CVE-2026-91840 https://bugzilla.redhat.com/show_bug.cgi?id=2533642 https://gitlab.gnome.org/Archive/NetworkManager-vpnc/-/work_items/19

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-91840? +

CVE-2026-91840 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0019, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-91840? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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