CVE-2016-3401 in Zimbra Collaboration
Summary
by MITRE
Unspecified vulnerability in Zimbra Collaboration before 8.7.0 allows remote authenticated users to affect integrity via unknown vectors, aka bug 99810.
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Analysis
by VulDB Data Team • 05/13/2026
The vulnerability identified as CVE-2016-3401 represents a security flaw within Zimbra Collaboration software prior to version 8.7.0 that enables remote authenticated attackers to compromise data integrity. This issue falls under the category of integrity violations where malicious actors can manipulate or corrupt data within the system without directly compromising confidentiality or availability. The vulnerability affects the core messaging platform that organizations rely upon for email and collaboration services, making it particularly concerning for enterprise environments. Zimbra Collaboration Suite serves as a comprehensive communication platform that includes email, calendar, contacts, and document sharing capabilities, making any integrity compromise potentially devastating to business operations.
The technical nature of this vulnerability stems from unspecified attack vectors that allow authenticated users to manipulate system data in ways that undermine the integrity of the platform. While the exact technical implementation details remain unspecified, such vulnerabilities typically arise from insufficient input validation, improper access controls, or flawed data processing mechanisms within the application. The fact that this is an authenticated vulnerability suggests that attackers must first establish valid credentials, but once authenticated, they can leverage the flaw to alter data or system states. This classification aligns with CWE-340 which addresses weaknesses in integrity verification mechanisms, particularly when authentication bypasses or weak integrity checks exist. The vulnerability's presence in versions before 8.7.0 indicates that it was a known issue that required patching through the software update process.
From an operational perspective, this vulnerability creates significant risk for organizations using Zimbra Collaboration Suite as their primary email and collaboration platform. The ability to affect data integrity means that attackers could potentially modify email content, calendar entries, contact information, or other critical collaboration data without detection. This could lead to business disruption, regulatory compliance violations, and potential financial losses due to compromised information. The remote nature of the attack means that threat actors do not require physical access to the network or system, making the vulnerability particularly dangerous. Organizations may experience data corruption that impacts business continuity, as well as potential legal and regulatory consequences if sensitive information is altered or manipulated. The impact extends beyond individual user data to encompass entire organizational communication channels that depend on the integrity of the platform.
The mitigation strategy for CVE-2016-3401 primarily involves upgrading to Zimbra Collaboration Suite version 8.7.0 or later, which contains the necessary patches to address the integrity vulnerability. Organizations should also implement robust monitoring and logging mechanisms to detect any suspicious activities that might indicate exploitation attempts. Network segmentation and access control measures can help limit the potential impact if an attacker does manage to exploit the vulnerability. Security teams should conduct thorough vulnerability assessments to ensure that all instances of the vulnerable software are identified and updated. Additionally, implementing multi-factor authentication and regular security audits can provide additional layers of protection. The vulnerability's classification under ATT&CK framework would likely map to techniques involving data manipulation or integrity compromise, emphasizing the need for proper data validation and integrity checking mechanisms. Organizations should also review their incident response procedures to ensure readiness for potential exploitation of this type of vulnerability.