Netgate pfSense Plus/pfSense CE Monitoring page status_monitoring.php injection

Summaryinfo

A vulnerability has been found in Netgate pfSense Plus and pfSense CE and classified as critical. Affected by this issue is some unknown functionality of the file status_monitoring.php of the component Monitoring page. This manipulation of the argument graph-left/graph-right/time-period/resolution/start-date/end-date/start-time/end-time/graph-type/invert/refresh-interval causes injection. This vulnerability appears as CVE-2026-56126. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in Netgate pfSense Plus and pfSense CE (the affected version unknown) and classified as critical. Affected by this vulnerability is an unknown part of the file status_monitoring.php of the component Monitoring page. The manipulation of the argument graph-left/graph-right/time-period/resolution/start-date/end-date/start-time/end-time/graph-type/invert/refresh-interval with an unknown input leads to a injection vulnerability. The CWE definition for the vulnerability is CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

pfSense Plus before 26.07 and CE before 2.9.0 allow authenticated users with the Status: Monitoring privilege to inject arbitrary JavaScript via graph configuration parameters in /status_monitoring.php. Multiple POST parameters including graph-left, graph-right, time-period, resolution, start-date, end-date, start-time, end-time, graph-type, invert, and refresh-interval are concatenated and written to the global pfSense XML configuration without sanitization, then echoed unsanitized into a JavaScript string context on page render. Because the setting is stored in the global configuration, the payload executes in the browser of every user who visits the Status: Monitoring page.

It is possible to read the advisory at docs.netgate.com. This vulnerability is known as CVE-2026-56126 since 06/18/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/03/2026). The attack technique deployed by this issue is T1055 according to MITRE ATT&CK.

By approaching the search of inurl:status_monitoring.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• Firewall Software

Vendor

• Netgate

Name

• pfSense CE
• pfSense Plus

License

• open-source

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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