CVE-2025-0767 in WP Activity Log
Summary
by MITRE • 02/27/2025
WP Activity Log 5.3.2 was found to be vulnerable. Unvalidated user input is used directly in an unserialize function in myapp/classes/Writers/class-csv-writer.php.
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Analysis
by VulDB Data Team • 02/27/2025
The vulnerability identified in WP Activity Log version 5.3.2 represents a critical security flaw that stems from improper input validation within the application's serialization handling mechanisms. This issue resides in the myapp/classes/Writers/class-csv-writer.php file where user-provided data is directly passed to an unserialize function without adequate sanitization or validation. The flaw creates a potential pathway for malicious actors to execute arbitrary code through crafted input that gets processed by the unserialize function, fundamentally compromising the integrity and security posture of the affected WordPress installation.
This vulnerability aligns with CWE-502, which specifically addresses "Deserialization of Untrusted Data" and falls under the broader category of insecure deserialization flaws that have been increasingly targeted in web application attacks. The improper handling of user input in this context creates a direct attack surface where malicious payloads can be constructed to exploit the unserialize function, potentially leading to remote code execution or privilege escalation within the affected system. The vulnerability's impact is particularly concerning given that it occurs within a logging and monitoring component, which typically operates with elevated privileges and has access to sensitive system information.
The operational implications of this vulnerability extend beyond simple code execution, as it can enable attackers to manipulate the logging functionality itself, potentially leading to log poisoning or complete bypass of security monitoring systems. Attackers could leverage this flaw to inject malicious serialized objects that would be processed during CSV export operations, creating a persistent threat vector that could remain undetected for extended periods. This type of vulnerability is particularly dangerous in enterprise environments where activity logs serve as critical security controls for monitoring and forensic analysis.
Mitigation strategies should prioritize immediate patching of the affected WP Activity Log plugin to version 5.3.3 or later, which contains the necessary fixes for this deserialization vulnerability. Organizations should also implement network-level restrictions to limit access to the plugin's CSV export functionality, particularly when it involves user input processing. Additionally, implementing proper input validation and sanitization measures at the application level, including the use of allowlists for acceptable input formats, can significantly reduce the attack surface. Security teams should also consider deploying web application firewalls and monitoring for unusual serialization patterns that may indicate exploitation attempts, aligning with ATT&CK technique T1566 for credential access through malicious file execution. Regular security audits of third-party plugins and core applications remain essential for identifying similar vulnerabilities that could compromise system integrity and data security.