CVE-2016-3410 in Zimbra Collaboration
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Zimbra Collaboration before 8.7.0 allow remote attackers to inject arbitrary web script or HTML via unspecified vectors, aka bugs 103956, 103995, 104475, 104838, and 104839.
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Analysis
by VulDB Data Team • 05/13/2026
The vulnerability identified as CVE-2016-3410 represents a critical cross-site scripting flaw affecting Zimbra Collaboration software versions prior to 8.7.0. This vulnerability encompasses multiple distinct XSS vectors that collectively impact the email and collaboration platform's security posture. The affected versions contain unspecified input validation mechanisms that fail to properly sanitize user-supplied data before rendering it within web interfaces. These vulnerabilities were tracked internally as bugs 103956, 103995, 104475, 104838, and 104839, indicating a coordinated effort to address multiple attack surfaces within the application's web components.
The technical exploitation of these XSS vulnerabilities occurs when remote attackers can inject malicious scripts or HTML content into the Zimbra interface through various input fields or parameters. The flaw stems from insufficient sanitization of user input within the application's web rendering components, allowing attackers to bypass security controls that should prevent execution of malicious code. This vulnerability specifically affects the web-based administration console and user interfaces where user-provided data is directly incorporated into HTML responses without proper encoding or validation. The attack vectors likely include email content fields, administrative configuration parameters, and user profile inputs that are processed and displayed without adequate security measures.
The operational impact of these vulnerabilities is significant as they enable attackers to execute arbitrary scripts within the context of authenticated user sessions. Successful exploitation could allow attackers to steal session cookies, perform unauthorized actions on behalf of users, redirect victims to malicious sites, or extract sensitive information from the Zimbra environment. The remote nature of these attacks means that attackers do not require physical access to the system or local network privileges to exploit the vulnerability. These XSS flaws could facilitate credential theft, data exfiltration, and privilege escalation attacks that compromise the integrity and confidentiality of email communications within the affected organization's collaboration infrastructure. The vulnerability affects both administrative and user interfaces, potentially enabling attackers to gain elevated privileges or access sensitive administrative functions.
Mitigation strategies for CVE-2016-3410 should prioritize immediate deployment of Zimbra Collaboration 8.7.0 or later versions that contain patches addressing these XSS vulnerabilities. Organizations should implement comprehensive input validation and output encoding mechanisms across all user-facing interfaces to prevent similar issues in the future. Security measures including content security policies, proper HTML encoding of user-supplied data, and regular security assessments of web applications should be implemented. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in software applications. From an ATT&CK framework perspective, this vulnerability maps to T1059.005 for command and scripting interpreter and T1566 for credential access through phishing and social engineering techniques that leverage XSS capabilities. Organizations should also consider implementing web application firewalls and monitoring for suspicious script injection patterns to detect potential exploitation attempts.