CVE-2022-3894 in WP OAuth Server Plugin
Summary
by MITRE • 03/20/2023
The WP OAuth Server (OAuth Authentication) WordPress plugin before 4.2.5 does not have CSRF check when deleting a client, and does not ensure that the object to be deleted is actually a client, which could allow attackers to make a logged in admin delete arbitrary client and post via a CSRF attack.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 02/26/2025
The WP OAuth Server plugin for WordPress represents a critical authentication mechanism that facilitates OAuth 2.0 protocol implementation across WordPress sites. This vulnerability affects versions prior to 4.2.5 and exposes a fundamental flaw in the plugin's security architecture. The issue manifests through the absence of proper Cross-Site Request Forgery (CSRF) protection mechanisms during client deletion operations, creating a pathway for malicious actors to exploit administrative privileges.
The technical flaw lies in the plugin's failure to implement adequate validation checks when processing client deletion requests. Specifically, the system does not verify that the deletion request originates from a legitimate administrative session or that the target object is indeed a client resource. This omission creates a scenario where an attacker can craft malicious requests that appear to come from authenticated administrators, thereby bypassing the intended security controls. The vulnerability extends beyond simple client deletion to potentially allow arbitrary post deletion, amplifying the attack surface significantly.
From an operational impact perspective, this vulnerability represents a severe threat to WordPress site integrity and security. An attacker who successfully exploits this CSRF flaw can manipulate the OAuth authentication system to remove legitimate client applications and potentially delete content from the WordPress site. The attack requires only that a logged-in administrator visits a malicious webpage or clicks on a crafted link, making it particularly dangerous in environments where administrators frequently browse external sites. This vulnerability directly relates to CWE-352, which specifically addresses Cross-Site Request Forgery issues in software applications.
The exploitation of this vulnerability can lead to significant consequences including unauthorized access to OAuth-protected resources, disruption of legitimate authentication flows, and potential data loss through post deletion capabilities. Security professionals should note that this issue aligns with ATT&CK technique T1566.002, which covers spearphishing via web applications, as attackers can leverage this vulnerability to manipulate authenticated sessions. Organizations using vulnerable versions of the WP OAuth Server plugin face immediate risk of compromise, particularly in environments where administrative privileges are frequently used or where administrators may be targeted through social engineering campaigns.
Mitigation strategies should focus on immediate plugin updates to version 4.2.5 or later, which addresses the CSRF validation gaps. Additionally, administrators should implement network-level protections such as web application firewalls that can detect and block suspicious deletion requests. Regular security auditing of WordPress plugins and maintaining updated security practices remain essential defensive measures. The vulnerability highlights the importance of implementing proper input validation and CSRF protection mechanisms in all administrative interfaces, particularly those handling sensitive operations like client management and content deletion.