Description
A critical vulnerability has been identified in the Hunk Companion plugin for WordPress that allows unauthorized plugin installation and activation due to missing capability checks on the /wp-json/hc/v1/themehunk-import REST API endpoint. This flaw is present in all versions up to and including 1.8.4, enabling unauthenticated attackers to install and activate arbitrary plugins that could be leveraged for remote code execution if another vulnerable plugin is activated.
Affected Product(s)
- Hunk Companion Plugin for WordPress – Versions up to and including 1.8.4
Technical Details
The Hunk Companion plugin is designed to enhance the functionality of ThemeHunk themes. However, due to a missing capability check on the /wp-json/hc/v1/themehunk-import REST API endpoint, the plugin is vulnerable to unauthorized plugin installation and activation. This endpoint is intended to facilitate the importation of theme data but lacks the necessary restrictions to limit its use to authenticated and authorized users.
This vulnerability carries a CVSS v3 base score of 9.8, categorizing it as critical, and a CVSS v2 score of 10.0, indicating severe impact. Essentially, any unauthenticated actor with knowledge of the endpoint can exploit the vulnerability to install and activate plugins arbitrarily. The exploit mechanism follows these steps:
- The attacker sends a crafted HTTP request to the /wp-json/hc/v1/themehunk-import endpoint.
- Due to the missing capability check, the request is processed without verifying the user’s authentication or permissions.
- The plugin specified in the request is installed and activated on the target WordPress instance.
Considering that many additional plugins could have their own vulnerabilities, this primary vulnerability in the Hunk Companion plugin could be the initial step in a more extensive exploitation chain. If another plugin with known vulnerabilities is activated through this exploit, the attacker could achieve remote code execution on the WordPress site.
Several versions of the plugin, from 1.2.2 to 1.8.4, are susceptible to this defect. Exploitation in the wild has already been observed, suggesting that attackers are actively leveraging this vulnerability in real-world scenarios.
The combination of wide-spread deployment of WordPress, the popularity of ThemeHunk themes, and the critical nature of the flaw makes this a significant security risk. Detailed narrative of the vulnerability and its potential exploitations can be found in various threat reports and advisories, including those published by Wordfence and other cybersecurity firms.
The rapid dissemination of information through platforms like Twitter and GitHub highlights the urgency and severity of the threat. Observations suggest that scanning and exploitation activities may lead to further compromises, especially when other vulnerable plugins are present on the same installation.
In conclusion, this vulnerability underscores the importance of conducting proper security reviews and implementing robust authentication and authorization checks within software components. The widespread impact and ease of exploitation make it a severe threat that requires immediate attention and remediation.
Weakness
The vulnerability is primarily associated with Missing Authorization (CWE-862), where the application fails to verify that the user has the necessary permissions to perform a sensitive action. In this case, the Hunk Companion plugin lacks the checks needed to ensure that only authenticated and authorized users can install and activate plugins via the provided REST API endpoint.
Impact Assessment
If exploited, this vulnerability could allow an attacker to gain unauthorized access to install and activate arbitrary plugins on a WordPress site. This could lead to remote code execution, especially if another activated plugin has its own security flaws. Consequently, attackers could execute arbitrary commands, deface the website, steal sensitive information, or further compromise the system’s integrity and confidentiality.
Active Exploitation
We have observed activity that indicates exploitation of this vulnerability in the wild. Attackers are utilizing this flaw to compromise WordPress sites by installing unsolicited plugins that may contain backdoors or other malicious payloads. This active exploitation underscores the urgency with which users of the Hunk Companion plugin must address this security issue to avoid potential breaches.
Ransomware Association
While there are no direct associations with specific ransomware variants linked to this vulnerability as of now, the potential for exploitation in ransomware attacks is significant. Attackers could use the unauthorized access to install plugins that facilitate data exfiltration or the deployment of ransomware payloads, thus compromising the site and its data.
Mitigation and Resolution
We have released a patch that addresses this vulnerability. Users of the Hunk Companion plugin should immediately update to version 1.8.5 or later to mitigate the risk. This update includes capability checks that prevent unauthorized users from installing or activating plugins through the vulnerable endpoint.
Recommendations
- We strongly recommend that all customers apply the latest patch as soon as possible.
- Update the Hunk Companion plugin to version 1.8.5 or newer immediately.
- Regularly review and update all installed plugins to ensure they are up-to-date and secure.
- Implement security measures to restrict access to REST API endpoints to authenticated and authorized users only.
- Conduct regular security audits of your WordPress installation and its plugins to identify and mitigate potential vulnerabilities.
- Monitor server logs for unusual activity that may indicate attempted exploitation of this vulnerability.
Referencesย
- CVE MITRE Details
- NVD Details
- GitHub Plugins
- WordPress Plugins
- WordPress Plugin: Hunk_Companion
- WordFence Threat Intel