CVE-2016-0903 in Avamar Server
Summary
by MITRE
Avamar Data Store (ADS) and Avamar Virtual Edition (AVE) in EMC Avamar Server before 7.3.0-233 rely on client-side authentication, which allows remote attackers to spoof clients and read backup data via a modified client agent.
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Analysis
by VulDB Data Team • 09/19/2022
The vulnerability identified as CVE-2016-0903 affects EMC Avamar Server components including Avamar Data Store and Avamar Virtual Edition across versions prior to 7.3.0-233. This security flaw represents a critical weakness in the authentication mechanism that governs access to backup data within the Avamar environment. The vulnerability stems from the system's reliance on client-side authentication rather than implementing robust server-side verification mechanisms, creating an exploitable gap in the security architecture that adversaries can leverage to gain unauthorized access to sensitive backup information.
The technical flaw manifests through the system's insufficient validation of client authenticity, allowing remote attackers to manipulate client agent software and present false credentials to the backup server. This weakness enables attackers to spoof legitimate client connections and gain read access to backup data stored within the Avamar infrastructure. The vulnerability operates at the application layer and can be exploited remotely without requiring physical access to the system, making it particularly dangerous for organizations relying on Avamar for critical data protection. The flaw essentially undermines the fundamental principle of secure authentication by failing to verify client identity at the server level, instead trusting potentially compromised client-side components to maintain security boundaries.
The operational impact of this vulnerability extends beyond simple data theft, as unauthorized access to backup data can lead to complete data compromise and potential business disruption. Attackers exploiting this vulnerability can access sensitive backup files, potentially including personally identifiable information, financial data, or proprietary corporate information depending on the organization's backup content. The remote nature of the attack means that threat actors can exploit this weakness from anywhere on the network, making detection and prevention more challenging. Organizations may experience significant regulatory and compliance implications if backup data containing sensitive information is accessed by unauthorized parties, potentially violating data protection regulations such as gdpr or hipaa depending on the data type and jurisdiction.
Mitigation strategies for this vulnerability require immediate implementation of the vendor-provided security patches and updates to Avamar Server versions 7.3.0-233 or later, which address the client-side authentication weakness through enhanced server-side validation mechanisms. Organizations should also implement network segmentation and access controls to limit exposure of Avamar components to untrusted networks, while establishing robust monitoring and logging of backup system access to detect anomalous authentication patterns. Additional defensive measures include implementing network-based intrusion detection systems to monitor for suspicious client agent behavior and establishing strict change management procedures for client-side software updates. The vulnerability aligns with CWE-287, which addresses improper authentication issues, and corresponds to attack techniques in the MITRE ATT&CK framework related to credential access and privilege escalation. Organizations should conduct thorough security assessments of their Avamar implementations to identify all affected systems and ensure complete remediation across their backup infrastructure.