Introduction
Attackers with even the lowest level of WordPress access can escalate privileges and install arbitrary plugins on sites using the B Slider Gutenberg Slider Block for WP plugin. This vulnerability has the potential to turn a simple subscriber account into a launchpad for full site compromise and remote code execution.
B Slider is a plugin available from the official WordPress repository, providing slider functionality for Gutenberg-based sites. It is popular among site owners seeking easy content presentation enhancements. The WordPress plugin ecosystem is vast and diverse, with security maturity varying widely among plugin developers. This context is important for understanding the risk landscape around third-party plugins like B Slider.
Technical Information
CVE-2025-8418 arises from missing capability checks in the activated_plugin function within the B Slider Gutenberg Slider Block for WP plugin. WordPress enforces a role-based access control model where only users with administrator privileges should be able to install or activate plugins. This is typically enforced by checking user capabilities (such as install_plugins or activate_plugins) before performing privileged actions.
In all versions up to and including 1.1.30, the B Slider plugin fails to check user capabilities in the activated_plugin function. As a result, any authenticated user with subscriber-level access or above can invoke this function and install arbitrary plugins. This is a direct violation of WordPress security best practices and represents a classic CWE-862 (Missing Authorization) issue.
A public code reference confirms the lack of capability checks:
// Reference: https://plugins.trac.wordpress.org/browser/b-slider/tags/1.1.28/adminMenu.php#L124 function activated_plugin() { // ... missing capability check ... // plugin installation logic }
Attackers can exploit this by sending crafted HTTP requests to endpoints that trigger the vulnerable function. Once arbitrary plugin installation is possible, an attacker can upload and activate a malicious plugin, leading to privilege escalation, data theft, or remote code execution.
Affected Systems and Versions
- Product: B Slider Gutenberg Slider Block for WP plugin for WordPress
- Affected versions: All versions up to and including 1.1.30
- Any WordPress installation with this plugin at or below version 1.1.30 is vulnerable
- The vulnerability can be exploited by any authenticated user with subscriber-level access or higher
Vendor Security History
There is no public record of previous major vulnerabilities in B Slider. However, similar missing authorization and privilege escalation issues have been documented in numerous other WordPress plugins. The plugin is maintained on the official WordPress repository, but the security maturity and patch response time of the vendor are not well established.