CVE-2026-1671 in Activity Log Plugin
Summary
by MITRE • 02/12/2026
The Activity Log for WordPress plugin for WordPress is vulnerable to unauthorized access of data due to a missing capability check on the winter_activity_log_action() function in all versions up to, and including, 1.2.8. This makes it possible for authenticated attackers, with Subscriber-level access and above, to view potentially sensitive information (e.g., the password of a higher level user, such as an administrator) contained in the exposed log files.
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Analysis
by VulDB Data Team • 02/13/2026
The vulnerability identified as CVE-2026-1671 affects the Activity Log plugin for WordPress, a widely used security monitoring tool that tracks user activities and system events within WordPress installations. This plugin serves as a critical component for administrators to monitor site activity and detect potential security breaches. The flaw resides in the winter_activity_log_action() function which fails to properly validate user permissions before exposing sensitive log data. The vulnerability exists in all versions up to and including 1.2.8, representing a significant security gap that undermines the plugin's intended purpose of providing security monitoring while simultaneously creating an attack vector for malicious actors.
The technical implementation of this vulnerability stems from a missing capability check within the plugin's codebase, specifically in the winter_activity_log_action() function. This function is designed to handle activity log actions but lacks proper authorization validation that would normally verify whether the requesting user possesses sufficient privileges to access the requested information. According to CWE-284, this represents an improper access control vulnerability where the system fails to properly enforce access restrictions, allowing unauthorized users to access resources they should not be permitted to view. The flaw enables authenticated attackers who have achieved at least Subscriber-level access to the WordPress site to bypass normal security controls and retrieve sensitive information from the activity logs.
The operational impact of this vulnerability is particularly concerning as it allows attackers to potentially access highly sensitive information that could compromise the entire WordPress installation. The exposure of administrator passwords or other elevated user credentials through activity log files creates a severe risk of privilege escalation attacks. Attackers can leverage this vulnerability to gain deeper access to the WordPress administration panel, potentially leading to complete site compromise. The attack vector requires only minimal privileges, making it particularly dangerous as it can be exploited by users who have already gained some level of access to the system. This aligns with ATT&CK technique T1078.004 which covers valid accounts used for unauthorized access, where attackers exploit legitimate access to escalate their privileges.
The vulnerability creates a direct pathway for credential theft and privilege escalation attacks, as the exposed log files may contain sensitive information such as administrator passwords, user session data, or other authentication tokens. This weakness fundamentally undermines the security model of WordPress installations that rely on the Activity Log plugin for monitoring and protection. Organizations using affected versions of this plugin face significant risk of data breaches, unauthorized access to administrative functions, and potential complete compromise of their WordPress sites. The vulnerability's persistence across multiple versions indicates a systemic issue in the plugin's security implementation that requires immediate attention and remediation.
Mitigation strategies should include immediate upgrading to the latest version of the Activity Log plugin where the capability check has been properly implemented. System administrators should also implement additional security measures such as monitoring for unusual access patterns, restricting user privileges where possible, and conducting regular security audits of plugin installations. The fix should ensure proper capability validation using WordPress's built-in permission systems, verifying that only users with appropriate administrative privileges can access sensitive log data. Organizations should also consider implementing network-level monitoring to detect potential exploitation attempts and establish incident response procedures for handling such security incidents.