Improper Neutralization of Argument Delimiters in a Command in OPNsense - CVE-2026-45158
Published: May 12, 2026
Vulnerability identifier: #VU131109
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-45158
CWE-ID: CWE-88
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary code as root.
The vulnerability exists due to improper neutralization of argument delimiters in the DHCP configuration handling in src/etc/inc/interfaces.inc when processing attacker-controlled DHCP hostname values through the web interface. A remote user can supply a crafted hostname value to execute arbitrary code as root.
Exploitation requires page-interfaces privileges and is triggered when changes are applied or when the interface later issues a DHCP request.
Affected software
OPNsense
How to mitigate CVE-2026-45158
Install security update from vendor's website.
OPNsense - update to 26.1.8