CVE-2026-91840 (GCVE-0-2026-91840)

Vulnerability from cvelistv5 – Published: 2026-09-25 17:56 – Updated: 2026-09-28 12:44
VLAI
Title
Networkmanager-vpnc: networkmanager-vpnc: local privilege escalation to root via newline injection in vpn username
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-26 03:55 UTC
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
fedora CNA under the redhat root
CNA scorecard C 69/100 over 44 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
GNOME NetworkManager-vpnc Affected: 0 , < * (semver)
guessed Create a notification for this product.
Date Public
2026-09-15 09:50
Credits
Red Hat would like to thank Andreas Gabriel Berbescu for reporting this issue.
Show details on NVD website
To clipboard 

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