CVE-2023-39305: Missing Authorization Vulnerability in YetAnotherStarsRating.com Exposes Exploitable Incorrectly Configured Access Control Security Levels

Yet Another Stars Rating (YASR) is a popular WordPress plugin that allows users to rate and review content on a site. With over 20,000 active installations, YASR has become an indispensable tool for many site owners. However, a newly disclosed vulnerability (CVE-2023-39305) in YASR may expose users' sites to potential attacks. In this post, we will discuss the details of this vulnerability, provide code snippets to demonstrate the issue, and offer guidance on how to mitigate this risk.

Vulnerability Details

This vulnerability affects YASR versions from n/a through 3.4.3, and stems from a missing authorization check in the plugin code. This oversight allows an attacker to exploit the plugin's incorrectly configured access control security levels and gain unauthorized access to a site's sensitive data or even modify the site's content.

Exploit Details

To exploit this vulnerability, an attacker must craft a specifically tailored HTTP request to a target site running a vulnerable version of YASR. This request, when executed, bypasses the plugin's access control security measures, giving the attacker unauthorized access to the site's backend.

Here's a sample code snippet that demonstrates the issue

// Vulnerable plugin code in YASR 3.4.3
function yasr_handle_rest_request($request) {
  // ... some functionality ...

  // Missing authorization check!
  $user_id = get_current_user_id();

  if ($user_id === ) {
    // This should return an error, but instead continues the execution
  }

  // ... some more functionality that allows unauthorized users to interact with the site ...
}

By removing the authorization check ($user_id === ), the code allows unauthorized access to the site's resources. This exposes the site to potential attacks where an attacker can leverage the vulnerability to modify data or compromise user accounts.

Mitigation

The immediate way to mitigate this vulnerability is to update YASR to the latest version that includes a patch addressing the issue. To do this, site owners should follow these steps:

Under 'Yet Another Stars Rating,' click 'Update Now.'

After updating, site owners should also ensure that their security settings are correctly configured to avoid further issues. This can be done by regularly reviewing access control policies, implementing least privilege principles, and testing new security features.

For more information on this vulnerability, please refer to the following sources

- YASR Official Changelog: (https://yetanotherstarsrating.com/changelog/)
- CVE Details: (https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-39305)
- WordPress Plugin Repository: (https://wordpress.org/plugins/yet-another-stars-rating/)

Conclusion

CVE-2023-39305 in the Yet Another Stars Rating plugin exposes websites to potential attacks and compromises due to a missing authorization vulnerability. Site owners should immediately update their YASR installation to the latest version and ensure their security practices are up-to-date. By staying vigilant and regularly reviewing security policies, site owners can protect their WordPress sites from similar vulnerabilities in the future.

Timeline

Published on: 12/13/2024 15:15:20 UTC