CVE-2017-8876 in Symphony
Summary
by MITRE
Symphony 2 2.6.11 has XSS in the meta[navigation_group] parameter to content/content.blueprintssections.php.
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Analysis
by VulDB Data Team • 12/06/2022
The vulnerability CVE-2017-8876 represents a cross-site scripting flaw discovered in Symphony 2 version 2.6.11 within the content/content.blueprintssections.php script. This issue specifically affects the meta[navigation_group] parameter, which is processed without proper input validation or output sanitization. The vulnerability exists in the content management system's blueprint section handling functionality where user-supplied data is directly incorporated into the application's response without adequate security measures.
The technical implementation of this vulnerability stems from insufficient sanitization of user input within the Symphony CMS framework. When the meta[navigation_group] parameter is submitted through the content/blueprintssections.php endpoint, the application fails to properly escape or validate the input before rendering it in the web page context. This allows malicious actors to inject arbitrary javascript code that executes in the context of other users' browsers who view the affected page. The vulnerability aligns with CWE-79 which defines Cross-Site Scripting as the improper handling of input data that is subsequently rendered in web pages without appropriate sanitization.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with the ability to perform session hijacking, steal user credentials, redirect users to malicious sites, or perform actions on behalf of authenticated users. The attack vector is particularly concerning because it targets the administrative interface of the CMS, potentially allowing attackers to gain elevated privileges or compromise the entire content management system. This vulnerability can be exploited through various means including crafted HTTP requests, social engineering attacks, or by leveraging other vulnerabilities that allow input injection into the affected parameter.
The exploitation of CVE-2017-8876 follows standard XSS attack patterns that align with ATT&CK technique T1059.007 for command and script injection. Attackers can craft malicious payloads that leverage the vulnerability to establish persistent access or perform privilege escalation within the CMS environment. The impact is amplified by the fact that Symphony CMS is often used for managing sensitive content and user data, making successful exploitation potentially devastating for organizations relying on this platform. Organizations may find that this vulnerability enables lateral movement within their network if the CMS is integrated with other systems or if attackers can leverage the compromised session to access additional resources.
Mitigation strategies for this vulnerability include immediate patching of the Symphony 2 CMS to version 2.6.12 or later which contains the necessary fixes for the XSS vulnerability. Additionally, organizations should implement proper input validation and output encoding mechanisms throughout their web applications, particularly in areas where user input is processed and rendered. Implementing Content Security Policy headers can provide additional protection against XSS attacks by restricting the sources from which scripts can be executed. Regular security audits and input validation testing should be conducted to identify similar vulnerabilities in other components of the application stack. Network segmentation and monitoring for suspicious traffic patterns can help detect exploitation attempts, while user education regarding the risks of clicking on untrusted links remains an important defensive measure. The vulnerability demonstrates the critical importance of proper input validation and output encoding practices as recommended by OWASP and other security frameworks to prevent XSS attacks that can compromise entire web applications.