CVE-2020-21316 in ZrLog
Summary
by MITRE • 06/16/2021
A Cross-site scripting (XSS) vulnerability exists in the comment section in ZrLog 2.1.3, which allows remote attackers to inject arbitrary web script and stolen administrator cookies via the nickname parameter and gain access to the admin panel.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 06/20/2023
The vulnerability identified as CVE-2020-21316 represents a critical cross-site scripting flaw within the ZrLog 2.1.3 content management system that exposes the application to remote code execution risks through user input manipulation. This vulnerability specifically targets the comment section functionality where the nickname parameter fails to properly sanitize user-provided input, creating an exploitable entry point for malicious actors seeking unauthorized access to administrative privileges.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding mechanisms within the ZrLog application's comment handling subsystem. When users submit comments containing malicious scripts in the nickname field, the application processes this input without sufficient sanitization measures, allowing the injected JavaScript code to execute within the context of other users' browsers. This flaw directly maps to CWE-79 which categorizes improper neutralization of input during web page generation as a primary cause of XSS vulnerabilities in web applications.
The operational impact of this vulnerability extends beyond simple script injection, as it enables attackers to steal administrator session cookies through the execution of malicious JavaScript code that can capture and exfiltrate authentication tokens. This capability provides attackers with persistent access to the administrative panel, allowing them to modify content, add malicious users, alter system configurations, and potentially escalate privileges within the application environment. The vulnerability's remote exploitability means that attackers can leverage this flaw from any location without requiring physical access to the server infrastructure.
The security implications of CVE-2020-21316 align with ATT&CK technique T1059.007 which describes the use of scripting languages for code execution, and T1566 which encompasses social engineering attacks through malicious web content. Organizations running ZrLog 2.1.3 are particularly vulnerable to coordinated attacks where threat actors can establish persistent access through this vector, potentially leading to complete system compromise. The vulnerability's exploitation can result in data breaches, unauthorized content modification, and the establishment of backdoor access points within the affected web environment.
Mitigation strategies for this vulnerability should include immediate implementation of input sanitization measures, output encoding of user-provided data, and the application of Content Security Policy headers to prevent unauthorized script execution. Organizations should also implement web application firewalls to detect and block malicious payloads targeting this specific vulnerability. The recommended remediation involves upgrading to a patched version of ZrLog or implementing proper input validation and output encoding mechanisms that prevent the execution of malicious scripts within the comment section functionality. Additionally, security monitoring should be enhanced to detect suspicious comment submissions that may indicate attempted exploitation of this vulnerability.