CVE-2026-25345: SimpLy Gallery Auth Bypass Vulnerability

CVE-2026-25345 Overview

CVE-2026-25345 is an Improper Validation of Specified Quantity in Input vulnerability affecting the GalleryCreator SimpLy Gallery WordPress plugin (simply-gallery-block). This flaw allows attackers to access functionality not properly constrained by Access Control Lists (ACLs), potentially leading to arbitrary code execution on affected WordPress installations.

Critical Impact

This vulnerability enables attackers to bypass access controls and execute arbitrary code on vulnerable WordPress sites running SimpLy Gallery plugin version 3.3.2 and earlier.

Affected Products

• GalleryCreator SimpLy Gallery (simply-gallery-block) versions through 3.3.2
• WordPress installations using the vulnerable plugin versions

Discovery Timeline

• 2026-03-25 - CVE-2026-25345 published to NVD
• 2026-03-25 - Last updated in NVD database

Technical Details for CVE-2026-25345

Vulnerability Analysis

This vulnerability stems from improper validation of input quantities within the SimpLy Gallery plugin for WordPress. The flaw is classified under CWE-1284 (Improper Validation of Specified Quantity in Input), which occurs when the application fails to properly validate numerical input values that specify quantities affecting program behavior or resource allocation.

The vulnerability allows attackers to access functionality that should be restricted by Access Control Lists. When exploited, this access control bypass can lead to arbitrary code execution, giving attackers the ability to compromise the WordPress installation and potentially the underlying server.

Root Cause

The root cause lies in the plugin's failure to properly validate and sanitize input values that specify quantities. When the application receives input representing a quantity (such as array sizes, iteration counts, or resource allocations), it does not adequately verify that the value falls within expected bounds or meets security constraints. This insufficient validation enables attackers to manipulate these values to bypass ACL restrictions and access protected functionality.

Attack Vector

The attack vector for this vulnerability targets WordPress sites with the SimpLy Gallery plugin installed. An attacker can craft malicious requests containing manipulated quantity values that bypass the plugin's access control mechanisms. By exploiting the improper input validation, the attacker gains access to functionality that should be restricted, ultimately enabling arbitrary code execution.

The attack does not require authentication in scenarios where the vulnerable functionality is exposed to unauthenticated users, though specific exploitation conditions may vary based on the WordPress site configuration and plugin settings.

Detection Methods for CVE-2026-25345

Indicators of Compromise

• Unusual HTTP requests to WordPress endpoints associated with the SimpLy Gallery plugin containing abnormal numeric parameters
• Unexpected file modifications or new files appearing in WordPress directories
• Anomalous process execution originating from the web server context
• Log entries showing access attempts to gallery-related functionality with malformed input values

Detection Strategies

• Monitor WordPress plugin directories for unauthorized file changes or suspicious uploads
• Implement Web Application Firewall (WAF) rules to detect and block requests with abnormal quantity parameters targeting gallery plugin endpoints
• Review access logs for patterns indicating ACL bypass attempts against the SimpLy Gallery plugin
• Deploy file integrity monitoring on WordPress installations to detect unauthorized modifications

Monitoring Recommendations

• Enable detailed logging for WordPress and web server access to capture request parameters
• Configure alerting for new file creation within WordPress plugin directories
• Monitor for unusual outbound network connections from the web server that may indicate post-exploitation activity
• Implement runtime application monitoring to detect code execution anomalies

How to Mitigate CVE-2026-25345

Immediate Actions Required

• Update the SimpLy Gallery plugin to a patched version as soon as one becomes available
• Consider temporarily disabling the SimpLy Gallery plugin until a patch is applied
• Review WordPress access logs for signs of exploitation attempts
• Implement WAF rules to filter malicious requests targeting the vulnerable plugin functionality

Patch Information

Administrators should monitor the Patchstack Vulnerability Advisory for updated patch information and remediation guidance. Update to a version newer than 3.3.2 when available from the plugin developer.

Workarounds

• Temporarily deactivate the SimpLy Gallery plugin until an official patch is released
• Restrict access to the WordPress admin panel and plugin functionality to trusted IP addresses only
• Implement strict input validation at the WAF level to block requests with suspicious quantity parameters
• Consider using alternative gallery plugins that are not affected by this vulnerability while awaiting a fix