CVE-2019-25371Public exploitNetwork attack vector

Reflected XSS via unencoded ping host parameter

Published Feb 15, 2026 · Updated Feb 15, 2026

Reflected XSS in diag_ping.php in Deciso B.V. OPNsense 19.1 allows remote attackers to run script in a user's browser via POST. The endpoint reflects the POST host parameter into its response without sufficient validation or output encoding. No account is required, but a user must render the crafted response; execution is confined to browser-accessible data in the OPNsense origin.

CVSS severity5.1
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in diag_ping.php in Deciso B.V. OPNsense 19.1 allows remote attackers to run script in a user's browser via POST. The endpoint reflects the POST host parameter into its response without sufficient validation or output encoding. No account is required, but a user must render the crafted response; execution is confined to browser-accessible data in the OPNsense origin.

The record

CVE
CVE-2019-25371
Published
Feb 15, 2026
Updated
Feb 15, 2026
Vendor
Deciso B.V.
Product
OPNsense
Classifications
CWE-79, CAPEC-591, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=19.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Deciso B.V. · OPNsenseversion=19.1

Published CVSS scores

5.1VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-591Reflected XSS
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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