CVE-2006-3102 in Bitweaver
Summary
by MITRE
Race condition in articles/BitArticle.php in Bitweaver 1.3, when run on Apache with the mod_mime extension, allows remote attackers to execute arbitrary PHP code by uploading arbitrary files with double extensions, which are stored for a small period of time under the webroot in the temp/articles directory.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 07/03/2024
The vulnerability identified as CVE-2006-3102 represents a critical race condition flaw within the Bitweaver 1.3 content management system that specifically affects installations running Apache with the mod_mime module. This vulnerability stems from improper file validation and handling mechanisms that create a temporal window during which malicious files can be processed and executed. The flaw occurs in the articles/BitArticle.php component where file uploads are managed, allowing attackers to exploit a timing gap in the file processing workflow.
The technical exploitation of this vulnerability relies on the manipulation of file extensions through a double extension technique, where files are named with extensions that appear legitimate but contain hidden malicious payloads. When an attacker uploads such a file, the system temporarily stores it in the temp/articles directory under the webroot, creating a window of opportunity for execution. This race condition typically occurs because the system does not properly validate file types during the upload process, instead relying on the web server's MIME type detection which can be bypassed through the double extension method. The mod_mime extension in Apache plays a crucial role in this attack vector as it determines file types based on their extensions, and the vulnerability exploits the inconsistency between the file extension and the actual file content.
The operational impact of this vulnerability is severe as it allows remote attackers to execute arbitrary PHP code on the affected server, potentially leading to complete system compromise. Attackers can upload malicious files that appear to be legitimate documents or images but contain PHP shellcode or backdoors. Once uploaded and processed during the brief window when files exist in the temporary directory, these malicious files can be executed by the web server, providing attackers with unauthorized access to the system. This vulnerability essentially transforms the file upload functionality into a remote code execution vector, making it particularly dangerous for web applications that rely on user-uploaded content. The attack can result in data theft, system infiltration, privilege escalation, and potential lateral movement within the network.
Mitigation strategies for this vulnerability should focus on implementing comprehensive file validation and sanitization mechanisms that prevent the upload of potentially malicious files. Organizations should immediately disable or remove the vulnerable Bitweaver 1.3 installation and upgrade to a patched version that addresses the race condition. The recommended approach includes implementing strict file type validation that checks both the file extension and the actual file content, rather than relying solely on extension-based detection. Additionally, the temporary storage directories should be secured with appropriate permissions and access controls to prevent execution of uploaded files. The system should also implement proper file naming conventions that prevent double extension attacks and ensure that uploaded files are processed through a secure validation pipeline before being stored in web-accessible directories. This vulnerability aligns with CWE-345 Insufficient Verification of Data Authenticity and ATT&CK technique T1059.007 Command and Scripting Interpreter PHP, highlighting the importance of proper input validation and secure file handling practices in web applications.