5.4
MEDIUM CVSS 3.1
CVE-2026-56128
pfSense Plus < 26.07 / CE < 2.9.0 Stored XSS via firewall_schedule_edit.php
Description

pfSense Plus before 26.07 and CE before 2.9.0 allow authenticated users with the Firewall: Schedules: Edit privilege to inject arbitrary JavaScript via the descr parameter in /firewall_schedule_edit.php. The schedule description is stored without HTML sanitization and subsequently inserted into an HTML attribute value in /firewall_rules.php with only single-quote escaping applied, permitting double-quote breakout. The payload executes in the browser of any user with the Firewall: Rules privilege who views the rules list with the affected schedule attached.

INFO

Published Date :

Sept. 3, 2026, 3:17 p.m.

Last Modified :

Sept. 3, 2026, 6:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-56128 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Netgate pfsense_plus
2 Netgate pfsense_ce
1 Pfsense pfsense
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update pfSense Plus or CE to patch the XSS vulnerability in firewall schedule descriptions.
  • Update pfSense Plus to version 26.07 or later.
  • Update pfSense CE to version 2.9.0 or later.
  • Sanitize user input for schedule descriptions.
  • Avoid inserting untrusted data into HTML attributes.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-56128 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-56128 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-56128 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-56128 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Sep. 03, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-56128', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-03T15:04:27.998871Z'}
  • New CVE Received by [email protected]

    Sep. 03, 2026

    Action Type Old Value New Value
    Added Description pfSense Plus before 26.07 and CE before 2.9.0 allow authenticated users with the Firewall: Schedules: Edit privilege to inject arbitrary JavaScript via the descr parameter in /firewall_schedule_edit.php. The schedule description is stored without HTML sanitization and subsequently inserted into an HTML attribute value in /firewall_rules.php with only single-quote escaping applied, permitting double-quote breakout. The payload executes in the browser of any user with the Firewall: Rules privilege who views the rules list with the affected schedule attached.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:P/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
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
    Added CWE CWE-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/56xxx/CVE-2026-56128.json">CVE-2026-56128</a>
    Added Reference https://docs.netgate.com/downloads/pfSense-SA-26_11.webgui.asc
    Added Reference https://docs.netgate.com/pfsense/en/latest/releases/2-9-0.html
    Added Reference https://docs.netgate.com/pfsense/en/latest/releases/26-07.html
    Added Reference https://www.vulncheck.com/advisories/pfsense-plus-ce-stored-xss-via-firewall-schedule-edit-php
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.