CVE-2018-16784 in DeDeCMS
Summary
by MITRE
DedeCMS 5.7 SP2 allows XML injection, and resultant remote code execution, via a "<file type='file' name='../" substring.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/26/2020
DedeCMS 5.7 SP2 contains a critical vulnerability that enables remote code execution through XML injection attacks, classified under CWE-94 as improper control of generation of code. The flaw exists in the system's handling of file operations where a specific substring pattern "<file type='file' name='../" can be exploited to manipulate XML data processing. This vulnerability arises from insufficient input validation and sanitization of user-supplied data within the content management system's file handling mechanisms, allowing attackers to inject malicious XML content that gets processed without proper security controls.
The technical exploitation of this vulnerability occurs when an attacker crafts malicious XML input containing the targeted substring pattern, which then gets interpreted by the DedeCMS system during file operations. This injection allows the attacker to manipulate the XML parser to execute arbitrary code on the server, effectively bypassing normal access controls and security boundaries. The vulnerability is particularly dangerous because it enables full remote code execution without requiring authentication, making it a severe threat to systems running this version of the content management system. The attack vector leverages the system's XML processing capabilities to inject code that executes in the context of the web server, potentially leading to complete system compromise.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise and data breach scenarios. Attackers can leverage this vulnerability to gain persistent access to affected systems, install backdoors, exfiltrate sensitive data, and use the compromised server as a launchpad for further attacks within the network. The vulnerability affects organizations using DedeCMS 5.7 SP2 across various deployment scenarios including web hosting environments, enterprise content management systems, and small business websites. According to ATT&CK framework, this vulnerability maps to T1059.007 for command and scripting interpreter and T1105 for remote file execution, representing the techniques used to establish and maintain persistent access.
Mitigation strategies for this vulnerability include immediate patching of the DedeCMS system to the latest available version that addresses the XML injection flaw. Organizations should implement comprehensive input validation and sanitization measures to prevent malicious XML content from being processed, including regular security audits of XML parsing functions and strict file access controls. Network segmentation and intrusion detection systems should be deployed to monitor for suspicious XML traffic patterns, while regular security assessments should be conducted to identify similar vulnerabilities in other system components. Additionally, implementing web application firewalls and restricting file upload capabilities can provide additional layers of protection against exploitation attempts. The vulnerability also underscores the importance of keeping content management systems updated and following secure coding practices to prevent similar injection vulnerabilities in future implementations.