CVE-2021-21079 in Connect
Summary
by MITRE • 03/13/2021
Adobe Connect version 11.0.7 (and earlier) is affected by a reflected Cross-Site Scripting (XSS) vulnerability. An attacker could exploit this vulnerability to inject malicious JavaScript content that may be executed within the context of the victim's browser when they browse to the page containing the vulnerable field.
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Analysis
by VulDB Data Team • 04/01/2021
Adobe Connect version 11.0.7 and earlier contains a reflected cross-site scripting vulnerability that represents a critical security risk for organizations relying on this web conferencing platform. This vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications. The flaw occurs when the application fails to properly sanitize user input before reflecting it back in HTTP responses, creating an opportunity for attackers to inject malicious scripts that execute in the context of other users' browsers. The vulnerability is particularly dangerous because it allows remote attackers to exploit the weakness without requiring authentication or privileged access to the system.
The technical implementation of this reflected XSS vulnerability stems from inadequate input validation and output encoding mechanisms within Adobe Connect's web interface. When users interact with the application and provide input through various parameters or fields, the system does not sufficiently filter or escape special characters that could be interpreted as executable code. Attackers can craft malicious URLs or form submissions that contain JavaScript payloads, which are then reflected back to the victim's browser when they navigate to the affected page. This creates a persistent threat vector where the malicious code executes with the privileges of the victim's browser session, potentially leading to complete account compromise or unauthorized access to sensitive conference data.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack chains that align with multiple tactics described in the MITRE ATT&CK framework. An attacker could leverage this vulnerability to perform session hijacking, steal authentication tokens, or redirect users to malicious websites that further exploit their browser sessions. The reflected nature of the vulnerability means that the attack payload must be delivered through a crafted URL or link that the victim must click, making social engineering a critical component of successful exploitation. Organizations using Adobe Connect in enterprise environments face significant risk of unauthorized access to sensitive meeting content, potential data exfiltration, and compromise of user credentials that could be used for broader network infiltration.
Organizations should immediately implement multiple layers of defense to mitigate this vulnerability while awaiting official patches from Adobe. The primary mitigation strategy involves implementing robust input validation and output encoding mechanisms at the application level, ensuring that all user-supplied data is properly sanitized before being reflected back to browsers. Network-based protections such as web application firewalls should be configured to detect and block known malicious patterns associated with XSS attacks. Additionally, organizations should implement content security policies that restrict script execution and prevent the loading of external resources that could contain malicious code. Regular security assessments and penetration testing should be conducted to identify other potential XSS vulnerabilities within the broader application ecosystem, as this vulnerability may indicate broader issues with input sanitization practices. The recommended remediation includes upgrading to Adobe Connect version 11.0.8 or later, which contains the necessary security patches to address this reflected XSS vulnerability.