CVE-2019-25374
CWE-79Published: February 15, 2026· Updated: Feb 18, 2026
Official Description
OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows attackers to inject malicious scripts by exploiting the passthrough_networks parameter in vpn_ipsec_settings.php. Attackers can craft POST requests with JavaScript payloads in the passthrough_networks parameter to execute arbitrary code in users' browsers.
Technical Analysis
CVE-2019-25374 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
A weaponized exploit for CVE-2019-25374 is publicly known. This significantly lowers the barrier for threat actors and increases the urgency for remediation.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (4)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2019-25374 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts