The WP iCal Availability plugin for WordPress, designed to help website owners share their availability through iCal format, has been found to have a Missing Authorization vulnerability. This vulnerability allows attackers to exploit Security Levels that have been incorrectly configured, potentially compromising the integrity and security of the web application.
This blog post will provide an in-depth analysis of the vulnerability, discuss the affected versions, share code snippets to explain the situation, and offer details on how the exploit works. Links to original references and resources will be provided throughout for further research.
Affected Versions
The Missing Authorization vulnerability affects WP iCal Availability versions up to and including 1..3. There is currently no available patch or update to address the vulnerability. Plugin users are advised to check for updates from the developers, monitor security advisories, and consider disabling the plugin as a mitigation step if necessary.
Exploit Details
In WP iCal Availability, the access control settings can be configured incorrectly, allowing attackers to bypass the intended security measures and gain unauthorized access to protected resources.
As a result, attackers can potentially modify the plugin's settings, read private data from calendars, and execute malicious code on the vulnerabilities that they discover.
For example, an attacker may exploit this vulnerability by sending HTTP requests to the vulnerable endpoint in the web application. A sample HTTP request exploiting the vulnerability may look like this:
POST /wp-admin/admin-ajax.php HTTP/1.1
Host: vulnerable-site.com
Content-Type: application/x-www-form-urlencoded
Content-Length: 74
action=wp_ical_availability_action&Calendar_URL=<?php_malicious_code_here?>
By sending this crafted request, the attacker can abuse the improperly configured access control settings in the plugin, execute arbitrary code, and compromise sensitive data.
Code Snippet
Here is a simplified code snippet demonstrating the vulnerability (taken from "wp-ical-availability.php" file):
add_action('wp_ajax_wp_ical_availability_action', 'wp_ical_availability_action_callback');
add_action('wp_ajax_nopriv_wp_ical_availability_action', 'wp_ical_availability_action_callback');
function wp_ical_availability_action_callback() {
// Vulnerable code without authorization check
$input = $_POST['Calendar_URL'];
// Code processing the input and generating output
echo $output;
wp_die();
}
The code above demonstrates that the plugin does not check for proper authorization before processing the Calendar_URL input. Without proper authorization checks, an attacker can bypass the intended safety measures and exploit this vulnerability.
For further information on this vulnerability, refer to the following resources
- CVE entry for CVE-2023-46607
- WP iCal Availability Plugin Homepage
Conclusion
The Missing Authorization vulnerability in WP iCal Availability versions up to and including 1..3 poses a serious security risk for WordPress websites using this plugin. Until a patch or update is released to address this issue, users should consider disabling the plugin and monitor security advisories closely. Furthermore, users should follow best practices for configuring access control settings in their web application to mitigate the risk of exploitation.
Timeline
Published on: 01/02/2025 12:15:12 UTC