CVE-2016-10148 in WordPress
Summary
by MITRE
The wp_ajax_update_plugin function in wp-admin/includes/ajax-actions.php in WordPress before 4.6 makes a get_plugin_data call before checking the update_plugins capability, which allows remote authenticated users to bypass intended read-access restrictions via the plugin parameter to wp-admin/admin-ajax.php, a related issue to CVE-2016-6896.
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Analysis
by VulDB Data Team • 05/13/2026
The vulnerability identified as CVE-2016-10148 represents a critical access control flaw within the WordPress content management system that affects versions prior to 4.6. This issue resides in the wp_ajax_update_plugin function located in the wp-admin/includes/ajax-actions.php file, where the application fails to properly validate user permissions before executing sensitive operations. The flaw specifically manifests when processing AJAX requests through the wp-admin/admin-ajax.php endpoint, creating a scenario where authenticated users can exploit a privilege escalation vulnerability through manipulation of the plugin parameter.
The technical implementation of this vulnerability stems from improper order of operations within the WordPress administrative AJAX handling mechanism. The function performs a get_plugin_data call before verifying whether the current user possesses the necessary update_plugins capability, which is a fundamental security principle that should be enforced prior to any data access operations. This sequence allows malicious actors to craft specially formatted requests that bypass the intended authorization checks, effectively granting them access to plugin information that should be restricted to users with appropriate administrative privileges.
From an operational perspective, this vulnerability enables authenticated attackers to perform unauthorized information disclosure attacks against WordPress installations. The bypass of read-access restrictions means that threat actors can potentially gather sensitive information about installed plugins, including version numbers, author details, and other metadata that could be used for further exploitation. This vulnerability directly relates to the broader category of privilege escalation issues and represents a specific instance of insufficient authorization checks that can be leveraged for reconnaissance purposes before attempting more sophisticated attacks.
The impact of this vulnerability extends beyond simple information disclosure, as it creates opportunities for attackers to gather intelligence about the target environment's plugin landscape. This information can be particularly valuable for attackers seeking to identify known vulnerabilities in specific plugin versions or to craft targeted attacks against particular plugin components. The flaw essentially undermines the principle of least privilege by allowing users with lower-level permissions to access plugin data that should be restricted to administrators or users with explicit update capabilities.
Security professionals should note that this vulnerability aligns with CWE-284 (Improper Access Control) and demonstrates characteristics consistent with ATT&CK technique T1068 (Exploitation for Privilege Escalation) and T1087 (Account Discovery). The flaw represents a classic case where the application's security controls are improperly ordered, allowing unauthorized access to sensitive data. Organizations should prioritize immediate patching of affected WordPress installations to remediate this vulnerability and prevent potential exploitation by threat actors who may be actively targeting WordPress environments.
Mitigation strategies should focus on immediate version upgrades to WordPress 4.6 or later, which contain the necessary security patches addressing this access control flaw. Additionally, organizations should implement monitoring for suspicious AJAX requests and unusual patterns of plugin data access attempts. Network-level controls can help detect and block malicious requests targeting the wp-admin/admin-ajax.php endpoint, while application-level security measures should enforce proper capability checks before any plugin data access operations occur. Regular security audits of WordPress installations should include verification of proper access control implementations and review of AJAX handling functions for similar vulnerabilities.