Stored Cross-Site Scripting (XSS) vulnerabilities can be a major security concern as they allow hackers to inject malicious scripts into otherwise trusted websites. Recently, a worrying vulnerability was discovered in the WHA WHA Puzzle plugin (versions <= 1..9) that could be exploited by attackers to perform Stored XSS attacks. As a responsible member of the cybersecurity community, this detailed post aims to elaborate on the specifics of this newly-identified CVE-2022-45839 vulnerability, along with the exploit details, so that developers and website administrators can take informed decisions to protect their properties.

Vulnerability Details - Stored Cross-Site Scripting in WHA WHA Puzzle

The CVE-2022-45839 vulnerability stems from improper sanitization of user input within the WHA WHA Puzzle plugin. This vulnerability is considered critical, as it allows an authenticated attacker, with contributor or higher privileges, to inject malicious scripts that can steal sensitive user data, trigger denial of service attacks, and vandalize the target website.

Affected Software

The vulnerability affects the WHA WHA Puzzle WordPress plugin up to version 1..9. Websites using this plugin should immediately update to the latest version in order to mitigate the risk of a possible Stored XSS attack.

Technical Details

The WHA WHA Puzzle plugin provides a shortcode for embedding puzzles on a website. The vulnerability is introduced when the shortcode attributes are not sanitized or escaped properly.

Here's a snippet of the vulnerable code within the "wha-wha-puzzle.php" file

extract(shortcode_atts(array(
'board_size' => 'normal',
'puzzle_id' => '',
'puzzle_shortcode' => '',
), $atts, 'wha_wha_puzzle'));

The shortcode attributes, $atts, are passed to the shortcode_atts() function without proper sanitization, posing a vulnerability.

Exploiting the Vulnerability

To exploit the CVE-2022-45839 vulnerability, an attacker who already has contributor or higher permissions on the target website can create a new post and insert a malicious script using the WHA WHA Puzzle shortcode like this:

[wha_wha_puzzle puzzle_id=<script>alert('XSS');</script>]

When other users/administrators/wp_posts table/query_posts previews this post, the injected script (in this case, <script>alert('XSS');</script>) will be executed, potentially causing harm (e.g., stealing sensitive data).

Mitigation

To mitigate the risk of CVE-2022-45839 vulnerability, update your WHA WHA Puzzle plugin to the latest version. In case a newer version is not available, you can apply a simple patch by modifying the "wha-wha-puzzle.php" file in the plugin directory and wrapping the $atts variable within the sanitize_text_field() function, like this:

$atts = array_map('sanitize_text_field', $atts);

This code change will help to sanitize the user input and prevent Stored XSS attacks.

Original References

- CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-45839
- WPScan Details: https://wpscan.com/vulnerability/eddaa1e-d992-4971-96a5-a5a55b614862

Conclusion

The CVE-2022-45839 Stored Cross-Site Scripting vulnerability in the WHA WHA Puzzle plugin is a serious security threat, and website administrators using the affected plugin versions should act promptly to protect their properties. By updating the plugin, applying a patch, or sanitizing user inputs more effectively, you can ensure that your website remains secure and resistant to Stored XSS attacks.

Timeline

Published on: 04/18/2023 13:15:00 UTC
Last modified on: 04/26/2023 20:30:00 UTC