CVE-2015-5731 in WordPress
Summary
by MITRE
Cross-site request forgery (CSRF) vulnerability in wp-admin/post.php in WordPress before 4.2.4 allows remote attackers to hijack the authentication of administrators for requests that lock a post, and consequently cause a denial of service (editing blockage), via a get-post-lock action.
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Analysis
by VulDB Data Team • 06/07/2022
The vulnerability described in CVE-2015-5731 represents a critical cross-site request forgery flaw within the WordPress content management system that specifically targets the administrative functionality of the platform. This issue exists in versions prior to 4.2.4 and exposes WordPress installations to malicious exploitation through unauthorized administrative actions. The vulnerability specifically affects the wp-admin/post.php file, which serves as the primary interface for post management within the WordPress admin dashboard. Attackers can leverage this weakness to manipulate the locking mechanism of posts, effectively gaining unauthorized control over administrative functions.
The technical implementation of this CSRF vulnerability stems from the absence of proper authentication verification mechanisms when processing post locking requests. When administrators access posts for editing, WordPress implements a locking system to prevent multiple users from editing the same post simultaneously. However, the vulnerability allows remote attackers to craft malicious requests that trigger the get-post-lock action without proper authentication checks. This flaw operates at the application layer and specifically targets the WordPress administrative interface, making it particularly dangerous for sites with active administrators who frequently manage content.
The operational impact of this vulnerability extends beyond simple privilege escalation to include significant denial of service conditions. When an attacker successfully hijacks an administrator's authentication session through the CSRF attack, they can lock posts that are crucial for site management and content editing. This creates an editing blockage that prevents legitimate administrators from accessing or modifying their content, effectively rendering the affected posts unusable for editing purposes. The attack requires minimal technical expertise and can be executed through simple web requests, making it particularly dangerous for widespread exploitation across multiple WordPress installations.
This vulnerability aligns with CWE-352, which specifically addresses Cross-Site Request Forgery vulnerabilities in software applications. The flaw demonstrates how insufficient validation of user requests can lead to unauthorized administrative actions within web applications. From an adversarial perspective, this vulnerability maps to ATT&CK technique T1078.004 which covers valid accounts and T1499.004 which involves network denial of service attacks. The attack vector operates through web-based exploitation where malicious actors can leverage existing administrator sessions to perform unauthorized actions against the WordPress installation.
The mitigation strategy for CVE-2015-5731 primarily involves immediate upgrading of WordPress installations to version 4.2.4 or later, which contains the necessary patches to address the CSRF vulnerability. Additionally, administrators should implement proper input validation and authentication checks for all administrative actions within their WordPress installations. Security measures such as implementing CSRF tokens for all administrative actions, enforcing strict session management, and utilizing security plugins that can detect and prevent such attacks provide additional layers of protection. Organizations should also conduct regular security audits of their WordPress installations to identify and remediate similar vulnerabilities before they can be exploited by malicious actors.