CVE-2016-2352 in File Transfer Appliance
Summary
by MITRE
The Accellion File Transfer Appliance (FTA) before FTA_9_12_40 allows remote authenticated users to execute arbitrary commands by leveraging the YUM_CLIENT restricted-user role.
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Analysis
by VulDB Data Team • 10/31/2024
The Accellion File Transfer Appliance represents a critical security vulnerability identified as CVE-2016-2352, which affects versions prior to FTA_9_12_40. This vulnerability specifically targets the YUM_CLIENT restricted-user role, creating a dangerous privilege escalation pathway that allows authenticated remote attackers to execute arbitrary commands on the affected system. The flaw exists within the appliance's access control mechanisms, where the restricted user role fails to properly enforce command execution boundaries, thereby enabling malicious actors to bypass intended security restrictions.
The technical implementation of this vulnerability stems from inadequate input validation and privilege separation within the appliance's command processing pipeline. When authenticated users with the YUM_CLIENT role attempt to interact with certain system components, the appliance fails to properly sanitize or restrict the commands they can submit, creating a command injection vulnerability that directly translates to arbitrary code execution. This issue manifests through the appliance's handling of user-supplied parameters that are subsequently processed without adequate security checks, allowing attackers to inject malicious commands that execute with elevated privileges.
From an operational perspective, this vulnerability presents a severe risk to organizations relying on Accellion FTA for secure file transfers, as it provides attackers with a direct path to compromise the entire appliance and potentially the underlying network infrastructure. The remote execution capability means that attackers do not require physical access or local network presence to exploit this vulnerability, significantly expanding the attack surface and making it particularly dangerous for environments where such appliances serve as critical security gateways. The impact extends beyond immediate system compromise to include potential data exfiltration, lateral movement opportunities, and disruption of legitimate file transfer operations.
Organizations should immediately implement mitigations including applying the vendor-provided patch to FTA_9_12_40 or later versions that address this vulnerability through proper privilege enforcement and input validation mechanisms. Network segmentation and access controls should be enhanced to limit unnecessary access to the appliance, while monitoring systems should be configured to detect suspicious command execution patterns. Additionally, security teams should conduct comprehensive vulnerability assessments to identify any potential exploitation attempts and ensure that all user accounts maintain appropriate access levels consistent with the principle of least privilege. This vulnerability aligns with CWE-78 and CWE-20 categories, representing command injection and input validation flaws respectively, and maps to attack techniques in the MITRE ATT&CK framework under privilege escalation and command execution domains.