CVE-2026-16057 in Contest Gallery Plugin
Summary
by MITRE • 08/03/2026
The Contest Gallery WordPress plugin before 30.0.7 does not perform per-object capability or nonce checks in one of its post-deletion handlers, gating it only by a coarse role-membership test, which allows any Author-level or higher user to permanently delete arbitrary posts, pages, and other content they do not own.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 08/03/2026
The Contest Gallery WordPress plugin vulnerability represents a critical authorization flaw that undermines the fundamental security model of content management systems. This issue affects versions prior to 30.0.7 and demonstrates a classic failure in implementing proper access control mechanisms within web applications. The vulnerability stems from insufficient validation checks in the plugin's post-deletion functionality, where the system relies solely on broad role-based membership tests rather than granular capability or nonce verification. Such a design flaw creates an exploitable condition that allows malicious actors with minimal privileges to perform unauthorized actions beyond their intended permissions.
The technical implementation of this vulnerability occurs within the plugin's post-deletion handlers where the system fails to verify whether users possess the specific capabilities required to delete particular objects. Instead of implementing per-object capability checks or nonce validation, the plugin only verifies that the user belongs to a role with sufficient privileges such as Author level or higher. This coarse-grained approach to access control violates fundamental security principles and creates a pathway for privilege escalation attacks. The absence of proper object-level authorization testing means that any user who has been granted Author status or above can delete content regardless of ownership, creating a significant risk for data integrity and content management security.
The operational impact of this vulnerability extends beyond simple unauthorized deletions and represents a serious threat to WordPress site integrity and user confidence. Attackers with Author privileges can systematically remove posts, pages, and other content that they do not own, potentially causing data loss, disruption of services, and compromise of sensitive information. This vulnerability particularly affects sites where multiple users with varying permission levels collaborate, as it allows for unauthorized manipulation of content across different user accounts. The implications become more severe in environments where the plugin manages contest entries, user-generated content, or other critical data that requires strict access controls to maintain proper governance and prevent malicious activities.
Security mitigation strategies for this vulnerability must address both immediate remediation and long-term architectural improvements to prevent similar issues in future implementations. The primary solution involves updating to Contest Gallery plugin version 30.0.7 or later, which includes proper per-object capability checks and nonce validation mechanisms that align with WordPress security best practices. Organizations should implement regular security audits of their WordPress plugins and themes to identify similar authorization flaws that could affect their systems. Additionally, administrators should enforce strict role-based access controls and monitor user activities for unauthorized content deletions. This vulnerability highlights the importance of implementing the principle of least privilege and proper object-level authorization checks as recommended in the CWE 284 category for improper access control. The issue also aligns with ATT&CK technique T1078 which involves valid accounts being used to perform unauthorized actions, emphasizing the need for robust access control mechanisms that go beyond simple role membership verification.
The broader implications of this vulnerability underscore the critical importance of proper authorization implementation in web applications and highlight common security pitfalls in plugin development. Many WordPress plugins fail to implement comprehensive access control measures, leaving systems vulnerable to exploitation by users with elevated privileges. This particular flaw demonstrates how insufficient security testing and code review can result in serious authorization bypass vulnerabilities that affect thousands of websites. Organizations should prioritize security testing during the software development lifecycle and ensure that all user actions are properly validated against specific capabilities rather than relying on broad role-based permissions. The vulnerability serves as a reminder that even seemingly simple operations like content deletion require robust security controls to prevent unauthorized access and data manipulation.