CVE-2021-42584 in Convos-Chat
Summary
by MITRE • 12/17/2021
A Stored Cross Site Scripting (XSS) issue exists in Convos-Chat before 6.32.
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Analysis
by VulDB Data Team • 12/23/2021
The vulnerability CVE-2021-42584 represents a stored cross site scripting flaw in Convos-Chat versions prior to 6.32, constituting a critical security weakness that enables attackers to execute malicious scripts within the context of affected user sessions. This vulnerability resides in the application's handling of user input that is subsequently stored and displayed without proper sanitization, creating an environment where malicious code can persist and propagate through the system. The affected software serves as a web-based chat application that facilitates real-time communication between users, making it a prime target for attackers seeking to exploit client-side vulnerabilities.
The technical implementation of this stored XSS vulnerability occurs when user-provided content containing malicious script tags is submitted to the Convos-Chat application and subsequently stored in the system's database or message storage mechanism. When other users view the affected content, the malicious scripts execute in their browsers, potentially leading to session hijacking, credential theft, or redirection to malicious sites. This type of vulnerability falls under CWE-79 which specifically addresses cross site scripting flaws, and operates as a persistent threat since the malicious code remains stored within the application's data stores rather than being temporary or reflected. The vulnerability's persistence makes it particularly dangerous as it can affect multiple users over extended periods without requiring repeated exploitation attempts.
The operational impact of CVE-2021-42584 extends beyond simple script execution, potentially enabling attackers to escalate privileges, access sensitive user data, or manipulate chat communications within the application. Attackers could leverage this vulnerability to steal session cookies, execute unauthorized commands, or redirect users to phishing sites that mimic legitimate chat interfaces. The implications are particularly severe in environments where Convos-Chat serves as a corporate communication platform, as it could compromise sensitive business communications and potentially lead to broader security breaches within the organization. This vulnerability aligns with ATT&CK technique T1531 which focuses on use of web shell for maintaining access and persistence.
Mitigation strategies for this vulnerability require immediate application of the vendor's security patch or upgrade to Convos-Chat version 6.32 or later, which includes proper input sanitization and output encoding mechanisms. Organizations should implement comprehensive input validation that filters or escapes potentially malicious content before storage, employ Content Security Policy headers to limit script execution, and conduct regular security testing of web applications. Additionally, security teams should monitor for indicators of compromise such as unusual network traffic patterns or unexpected user behavior that might suggest exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation and output encoding in preventing cross site scripting attacks, and serves as a reminder of the necessity for regular security updates and vulnerability assessments in web-based applications.