Description
OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.4, multiple OPNsense MVC API endpoints perform state‑changing operations but are accessible via HTTP GET requests without CSRF protection. The framework CSRF validation in ApiControllerBase only applies to POST/PUT/DELETE methods, allowing authenticated GET requests to bypass CSRF verification. As a result, a malicious website can trigger privileged backend actions when visited by an authenticated user, causing unintended service reloads and configuration changes through configd. This results in an authenticated Cross‑Site Request Forgery vulnerability allowing unauthorized system state changes. This vulnerability is fixed in 26.1.4.
Scores
CVSS v3
6.3
EPSS
0.0002
EPSS Percentile
5.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:L
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-352
Status
published
Products (1)
opnsense/opnsense
< 26.1.4
Published
Mar 11, 2026
Tracked Since
Mar 12, 2026