CVE-2025-11703

Executive Summary

CVE-2025-11703 is a Cache Poisoning vulnerability affecting the WP Go Maps (formerly WP Google Maps) plugin for WordPress, up to and including version 9.0.48. The vulnerability arises because the plugin does not serve cached data from server-side responses and instead relies on user-supplied input to generate cache keys. This allows an unauthenticated attacker to manipulate the cache for location search results, potentially serving malicious or stale content to other users. The vulnerability has a CVSS score of 5.3 (Medium) and an EPSS score of 0.0%, indicating low exploitation likelihood at this time. No public proof-of-concept (PoC) or exploit code is available.

WordPress Ecosystem Context

This vulnerability is specific to the WordPress ecosystem and the WP Go Maps plugin. It is not related to Apache or Nginx server configurations. The plugin's failure to properly sanitize and cache user input for location search results is the root cause.

CVSS Breakdown & Threat Level

• CVSS Score: 5.3 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
• Attack Vector (AV): Network (N) – The attack can be executed remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerable component and the impacted component are the same.
• Confidentiality (C): None (N) – No data exposure.
• Integrity (I): Low (L) – Cache poisoning can lead to serving modified content.
• Availability (A): None (N) – No denial of service.

Threat Level: Medium. While the impact is limited to integrity, the low attack complexity and lack of authentication make it a viable target for cache poisoning attacks.

Deep Dive & Mechanics

The WP Go Maps plugin provides a map and location search functionality. When a user performs a location search, the plugin constructs a cache key based on user-supplied input (e.g., search query parameters). The vulnerability lies in the fact that the plugin does not validate or sanitize this input before using it to generate the cache key. An attacker can craft a malicious request with a specially crafted search query that, when cached, will be served to subsequent users.

Mechanism:

1. An unauthenticated attacker sends a GET request to the WordPress site with a crafted search parameter (e.g., ?q=malicious_payload).
2. The plugin processes this input and generates a cache key based on the raw input.
3. The response (which may include attacker-controlled content) is stored in the cache.
4. Subsequent users who make the same search request receive the poisoned cache entry, potentially seeing manipulated map data or injected content.

Root Cause: The plugin uses user input directly in cache key generation without proper sanitization or server-side caching logic. This is a classic example of CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') in the context of cache poisoning.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is described below. A patched version would need to implement server-side caching with input validation.

Vulnerable Code (Conceptual):

// Vulnerable: Uses raw user input for cache key
$search_query = $_GET['q'];
$cache_key = 'wpgmaps_search_' . $search_query;
$cached_response = wp_cache_get($cache_key);
if ($cached_response === false) {
    // Generate response based on user input
    $response = generate_map_data($search_query);
    wp_cache_set($cache_key, $response);
}
echo $response;

Patched Code (Conceptual):

// Patched: Sanitize input and use server-side caching
$search_query = sanitize_text_field($_GET['q']);
$cache_key = 'wpgmaps_search_' . md5($search_query);
$cached_response = wp_cache_get($cache_key);
if ($cached_response === false) {
    // Generate response based on sanitized input
    $response = generate_map_data($search_query);
    wp_cache_set($cache_key, $response, 3600); // Set TTL
}
echo $response;

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• A WordPress site with WP Go Maps plugin version <= 9.0.48.
• Ability to send HTTP requests to the target.

Exploitation Steps:

1. Identify the search endpoint (e.g., /wp-json/wpgmaps/v1/search or a custom AJAX handler).
2. Craft a malicious search query that will be cached. For example:

   GET /?q=<script>alert('XSS')</script> HTTP/1.1
   Host: target.com
   

3. Send the request. The plugin will cache the response containing the injected script.
4. Subsequent users searching for the same query will receive the poisoned response.

Note: No public exploit code is available. The above is a conceptual demonstration.

Blue Team (Detection & Defense)

Detection:

• Monitor for unusual search query patterns, especially those containing HTML/JavaScript.
• Look for multiple requests with the same search query from different IPs (indicating cache poisoning propagation).
• Check cache entries for unexpected content.

Defense:

• Implement input validation and sanitization for all user-supplied data.
• Use server-side caching with proper key generation (e.g., hashing the input).
• Set appropriate cache TTLs to limit the impact of poisoned entries.
• Consider using a Web Application Firewall (WAF) to block malicious search queries.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests with suspicious search parameters (e.g., containing <script>, onerror=, etc.).
  • Repeated requests to the same search endpoint with identical query strings.
• File IOCs:
  • Modified cache files in the WordPress wp-content/cache/ directory containing unexpected content.
• Log IOCs:
  • Web server logs showing unusual search query patterns.
  • Application logs indicating cache hits for malicious queries.

Detection Engineering

YARA Rule

rule wp_go_maps_cache_poisoning {
    meta:
        description = "Detects cache poisoning attempts against WP Go Maps plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-11703"
    strings:
        $search_param = "q=" nocase
        $malicious_payload = /<script|<iframe|onerror=|javascript:/ nocase
    condition:
        $search_param and $malicious_payload
}

Sigma Rule

title: WP Go Maps Cache Poisoning Attempt
id: 8f3a4b2c-1d5e-4f6a-8b7c-9d0e1f2a3b4c
status: experimental
description: Detects HTTP requests with suspicious search parameters targeting WP Go Maps
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-11703
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-uri-query|contains: 'q='
        cs-uri-query|contains|all:
            - '<script'
            - 'onerror='
            - 'javascript:'
    condition: selection
falsepositives:
    - Legitimate search queries containing similar patterns (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"WP Go Maps Cache Poisoning Attempt"; flow:to_server; content:"q="; http_uri; content:"<script"; http_uri; content:"onerror="; http_uri; content:"javascript:"; http_uri; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the WP Go Maps plugin until a patch is available.
2. Clear all caches (browser, CDN, server-side) to remove any potentially poisoned entries.
3. Implement a Web Application Firewall (WAF) rule to block requests with suspicious search parameters.

Long-Term Fix:

• The vendor must release a patched version that implements server-side caching with input validation and proper cache key generation (e.g., using hashed inputs).
• Until then, consider using an alternative mapping plugin that is actively maintained.

Workaround:

• Modify the plugin code to sanitize search inputs before caching (not recommended for non-developers).
• Use a reverse proxy (e.g., Nginx) to cache responses only after validation.

Valters IT
Securing Digital Frontiers