CVE-2011-5208 in BackWPup
Summary
by MITRE
Multiple directory traversal vulnerabilities in the BackWPup plugin before 1.4.1 for WordPress allow remote attackers to read arbitrary files via a .. (dot dot) in the wpabs parameter to (1) app/options-view_log-iframe.php or (2) app/options-runnow-iframe.php.
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Analysis
by VulDB Data Team • 08/17/2017
The CVE-2011-5208 vulnerability represents a critical directory traversal flaw in the BackWPup WordPress plugin, affecting versions prior to 1.4.1. This vulnerability resides within the plugin's handling of user-supplied input in two specific PHP files that manage backup operations and log viewing functionalities. The flaw enables remote attackers to access arbitrary files on the web server by manipulating the wpabs parameter through directory traversal sequences using the .. (dot dot) notation. The vulnerability specifically impacts the app/options-view_log-iframe.php and app/options-runnow-iframe.php endpoints, which are integral components of the plugin's administrative interface for managing WordPress backups.
The technical exploitation of this vulnerability stems from inadequate input validation and sanitization within the BackWPup plugin's codebase. When the wpabs parameter is passed to these PHP scripts without proper validation, the application fails to restrict file access to the intended directories, allowing attackers to navigate beyond the intended file system boundaries. This directory traversal occurs because the plugin directly incorporates user input into file path resolution without implementing proper path normalization or access control mechanisms. The vulnerability aligns with CWE-22, which classifies directory traversal attacks as a fundamental weakness in input validation and access control, where insufficient restrictions on file system access enable unauthorized file retrieval.
The operational impact of CVE-2011-5208 is significant and multifaceted, potentially exposing sensitive system information to remote attackers. Successful exploitation could allow threat actors to access WordPress configuration files, database credentials, plugin files, and potentially even system-level files that contain sensitive information. The vulnerability's remote nature means attackers do not require local system access or credentials to exploit it, making it particularly dangerous in environments where WordPress installations are publicly accessible. Additionally, the exposure of log files through the view_log-iframe.php endpoint could reveal sensitive backup operations metadata, including backup schedules, file paths, and potentially authentication tokens or other operational details that could aid in further attacks.
Security professionals should consider this vulnerability in the context of the MITRE ATT&CK framework, particularly under the T1083 (File and Directory Discovery) and T1566 (Phishing) techniques, as attackers could use the information gained from directory traversal to plan more sophisticated attacks. The vulnerability demonstrates poor input validation practices that are commonly exploited in web application attacks, representing a failure to implement proper security controls at the application layer. Organizations running vulnerable versions of BackWPup should immediately implement patch management procedures to upgrade to version 1.4.1 or later, which includes proper input validation and sanitization mechanisms. Additional mitigations should include restricting access to administrative interfaces, implementing web application firewalls, and conducting comprehensive security audits of WordPress installations to identify similar vulnerabilities in other plugins or themes. The vulnerability also underscores the importance of maintaining up-to-date security practices and regular vulnerability assessments in WordPress environments to prevent exploitation of known weaknesses in third-party components.