CVE-2019-25368Public exploitNetwork attack vector

Administrator-session script execution via unescaped backup parameters

Published Feb 15, 2026 · Updated Feb 15, 2026

Reflected XSS in OPNsense 19.1 allows remote authenticated users to execute JavaScript in an administrator's browser via crafted POST data. The diag_backup.php form returns eight Google Drive and Nextcloud POST values inside HTML attributes without context-specific escaping. A crafted form must be submitted and its response rendered in an authenticated administrator session, limiting execution to that browser context.

CVSS severity4.8
Medium
EPSS probability0.14%
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 OPNsense 19.1 allows remote authenticated users to execute JavaScript in an administrator's browser via crafted POST data. The diag_backup.php form returns eight Google Drive and Nextcloud POST values inside HTML attributes without context-specific escaping. A crafted form must be submitted and its response rendered in an authenticated administrator session, limiting execution to that browser context.

The record

CVE
CVE-2019-25368
Published
Feb 15, 2026
Updated
Feb 15, 2026
Vendor
Deciso B.V.
Product
OPNsense
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

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 privilegesauthenticated

What is affected?

Deciso B.V. · OPNsenseversion=19.1

Published CVSS scores

5.4VulnCheckCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
4.8VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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