CVE-2020-16632 in DeDeCMS
Summary
by MITRE • 05/15/2021
A XSS Vulnerability in /uploads/dede/action_search.php in DedeCMS V5.7 SP2 allows an authenticated user to execute remote arbitrary code via the keyword parameter.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 05/16/2021
The vulnerability CVE-2020-16632 represents a critical cross-site scripting flaw within the DedeCMS content management system version 5.7 SP2, specifically affecting the /uploads/dede/action_search.php component. This issue arises from insufficient input validation and output sanitization mechanisms that fail to properly handle user-supplied data, creating a pathway for malicious actors to inject and execute arbitrary code within the target system. The vulnerability is particularly concerning because it requires only authenticated access, meaning that an attacker with valid credentials can exploit this flaw to compromise the entire CMS infrastructure.
The technical implementation of this vulnerability stems from improper handling of the keyword parameter within the search functionality of the administrative interface. When an authenticated user submits a search query containing malicious script code, the application fails to adequately sanitize this input before processing or displaying the results. This oversight creates a persistent XSS vector that can be leveraged to execute arbitrary JavaScript code within the context of the victim's browser session. The CWE-79 classification applies directly to this vulnerability, as it represents a failure to properly encode output data, allowing malicious scripts to be injected and executed in the user's browser.
The operational impact of CVE-2020-16632 extends beyond simple script injection, as authenticated users with administrative privileges can potentially escalate their access to full system compromise. Attackers can leverage this vulnerability to manipulate the CMS functionality, modify content, steal administrative credentials, or establish persistent backdoors within the system. The attack surface is particularly dangerous because it operates within the administrative interface where users have elevated privileges, making it possible for attackers to modify core system files, create new administrative accounts, or even gain shell access to the underlying server. This vulnerability directly maps to ATT&CK technique T1059.007 for command and scripting interpreter, as it allows for arbitrary code execution through script injection.
Mitigation strategies for CVE-2020-16632 must address both immediate remediation and long-term security improvements. The primary solution involves implementing proper input validation and output encoding mechanisms throughout the application, specifically within the search functionality and all administrative interfaces. Organizations should ensure that all user-supplied input undergoes rigorous sanitization before being processed or displayed, with special attention to parameters like keyword fields that are commonly used in search operations. Additionally, implementing proper access controls and privilege separation can limit the damage potential of authenticated attacks. Regular security audits and code reviews should be conducted to identify similar vulnerabilities in other components of the CMS. The DedeCMS development team has released patches addressing this vulnerability, and organizations should immediately apply these updates while also considering the implementation of web application firewalls and additional monitoring mechanisms to detect suspicious activities that might indicate exploitation attempts.