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.
OPNsense 19.1 Reflected XSS via monit interface
Problem type
Affected products
Opnsense
19.1 - AFFECTED
References
https://www.exploit-db.com/exploits/46351
https://opnsense.org
https://forum.opnsense.org/index.php?topic=11469.0
https://www.vulncheck.com/advisories/opnsense-reflected-xss-via-monit-interface
GitHub Security Advisories
GHSA-6333-cc9f-9589
OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated...
https://github.com/advisories/GHSA-6333-cc9f-9589OPNsense 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.
https://nvd.nist.gov/vuln/detail/CVE-2019-25375
https://forum.opnsense.org/index.php?topic=11469.0
https://opnsense.org
https://www.exploit-db.com/exploits/46351
https://www.vulncheck.com/advisories/opnsense-reflected-xss-via-monit-interface
https://github.com/advisories/GHSA-6333-cc9f-9589
JSON source
https://cveawg.mitre.org/api/cve/CVE-2019-25375Click to expand
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"cveId": "CVE-2019-25375",
"assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"assignerShortName": "VulnCheck",
"dateUpdated": "2026-02-15T13:58:56.731Z",
"dateReserved": "2026-02-15T13:21:00.205Z",
"datePublished": "2026-02-15T13:58:56.731Z",
"state": "PUBLISHED"
},
"containers": {
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"shortName": "VulnCheck",
"dateUpdated": "2026-02-15T13:58:56.731Z"
},
"datePublic": "2019-02-01T00:00:00.000Z",
"title": "OPNsense 19.1 Reflected XSS via monit interface",
"descriptions": [
{
"lang": "en",
"value": "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": [
{
"vendor": "Opnsense",
"product": "OPNsense",
"versions": [
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"version": "19.1",
"status": "affected"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"lang": "en",
"description": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
"cweId": "CWE-79",
"type": "CWE"
}
]
}
],
"references": [
{
"url": "https://www.exploit-db.com/exploits/46351",
"name": "ExploitDB-46351",
"tags": [
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},
{
"url": "https://opnsense.org",
"name": "OPNsense Official Website",
"tags": [
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},
{
"url": "https://forum.opnsense.org/index.php?topic=11469.0",
"name": "OPNsense 19.1.1 Release Announcement",
"tags": [
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},
{
"url": "https://www.vulncheck.com/advisories/opnsense-reflected-xss-via-monit-interface",
"name": "VulnCheck Advisory: OPNsense 19.1 Reflected XSS via monit interface",
"tags": [
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"metrics": [
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"availabilityImpact": "NONE",
"baseScore": 6.1,
"baseSeverity": "MEDIUM"
}
}
],
"solutions": [
{
"lang": "en",
"value": "OPNsense 19.1.1 released"
}
],
"credits": [
{
"lang": "en",
"value": "Ozer Goker",
"type": "finder"
}
]
}
}
}