CVE-2019-25375
OPNsense 19.1 Reflected XSS via monit interface
MEDIUM 5.1EPSS 0.4%
OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by submitting crafted input to the mailserver parameter. Attackers can send POST requests to the monit interface with JavaScript payloads in the mailserver parameter to execute arbitrary code in users' browsers.
- Affected
- Opnsense · OPNsense
- CVSS v4.0 VULNCHECK
- 5.1 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v3.1 VULNCHECK
- 6.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS
- 0.42% chance of exploitation in the next 30 days, 34th percentile
- Published
- 2026-02-15
- Updated
- 2026-05-24
Proof-of-concept exploits (1)
Security advisories
- https://www.vulncheck.com/advisories/opnsense-reflected-xss-via-monit-interface
- https://forum.opnsense.org/index.php?topic=11469.0
- https://opnsense.org