CVE-2017-14035 in CrushFTP
Summary
by MITRE
CrushFTP 8.x before 8.2.0 has a serialization vulnerability.
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Analysis
by VulDB Data Team • 11/12/2019
CrushFTP version 8.x prior to 8.2.0 contains a critical serialization vulnerability that exposes the application to remote code execution and arbitrary code injection attacks. This vulnerability stems from improper handling of serialized data within the application's object deserialization process, creating a pathway for malicious actors to execute arbitrary commands on the affected system. The flaw exists in the way CrushFTP processes serialized objects, particularly when handling user-provided data that gets deserialized without adequate validation or sanitization measures.
The technical implementation of this vulnerability allows attackers to craft malicious serialized objects that, when processed by the vulnerable CrushFTP server, trigger unintended code execution. This occurs because the application fails to implement proper input validation mechanisms during the deserialization phase, enabling attackers to inject malicious payloads that can manipulate the application's object graph. The vulnerability is particularly dangerous as it can be exploited remotely without authentication, making it accessible to any attacker who can send crafted requests to the FTP server. According to CWE classification, this represents a weakness in the deserialization process, specifically CWE-502 which covers deserialization of untrusted data, and aligns with ATT&CK technique T1059.007 for command and scripting interpreter.
The operational impact of this vulnerability extends beyond simple remote code execution, as it can lead to complete system compromise and persistent access for threat actors. Successful exploitation allows attackers to gain full control over the affected CrushFTP server, potentially enabling them to establish backdoors, exfiltrate sensitive data, or use the compromised system as a launch point for further attacks within the network. The vulnerability affects organizations using CrushFTP versions 8.0.0 through 8.1.9, making it a significant concern for businesses that rely on this FTP solution for file transfer operations. Organizations may experience data breaches, system downtime, and potential compliance violations depending on the sensitivity of the data handled by the compromised FTP server.
Mitigation strategies for this vulnerability should prioritize immediate patching to version 8.2.0 or later, which addresses the serialization flaw through proper input validation and sanitization of serialized data. Additionally, network segmentation and access controls should be implemented to limit exposure of the FTP service to only authorized users and systems. Organizations should also consider disabling unnecessary FTP features and implementing monitoring solutions to detect suspicious deserialization activities. Security professionals should review the application's configuration to ensure that object deserialization is properly restricted and that appropriate security headers are implemented. Regular security assessments and vulnerability scanning should be conducted to identify similar weaknesses in other applications and systems within the organization's infrastructure, as this type of vulnerability is commonly found in applications that improperly handle serialized data objects.