CVE-2021-20552 in Sterling File Gateway
Summary
by MITRE • 10/07/2021
IBM Sterling File Gateway 6.0.0.0 through 6.1.1.0 could allow a remote attacker to obtain sensitive information when a detailed technical error message is returned in the browser. This information could be used in further attacks against the system. IBM X-Force ID: 199170.
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Analysis
by VulDB Data Team • 10/10/2021
IBM Sterling File Gateway versions 6.0.0.0 through 6.1.1.0 contain a vulnerability that exposes sensitive system information through detailed error messages returned to web browsers. This flaw represents a classic information disclosure vulnerability where the application fails to properly sanitize error responses, potentially revealing internal system details such as file paths, system configurations, or stack traces. The vulnerability falls under CWE-209, which specifically addresses the exposure of error information that could aid attackers in understanding the system architecture and identifying potential attack vectors. When a remote attacker triggers an error condition within the file gateway system, the application's response includes verbose technical details that should not be exposed to end users or external parties.
The operational impact of this vulnerability extends beyond simple information leakage, as the exposed technical details can significantly aid in subsequent attack phases according to the MITRE ATT&CK framework's T1068 technique for Local Privilege Escalation and T1083 for File and Directory Discovery. Attackers can leverage the disclosed information to craft more targeted attacks, potentially identifying system weaknesses, understanding the underlying infrastructure, and planning further exploitation attempts. The vulnerability particularly affects the web interface components of the Sterling File Gateway, making it accessible to remote attackers without requiring authentication or specialized privileges. This makes the attack surface significantly larger as the information disclosure occurs during normal application error handling processes.
The security implications of this vulnerability are compounded by the fact that IBM Sterling File Gateway is designed for enterprise file transfer and management, making it a critical component in many organizations' infrastructure. The exposed information could reveal internal network structures, application version details, or configuration parameters that would otherwise remain hidden from external observers. Organizations using these vulnerable versions face increased risk of targeted attacks, including potential exploitation of additional vulnerabilities that might be discovered through the leaked information. The vulnerability demonstrates poor security hygiene in error handling practices, where the application's defensive mechanisms fail to properly isolate sensitive operational details from user-facing responses.
Mitigation strategies should focus on implementing proper error handling mechanisms that sanitize all error responses before transmission to client systems. Organizations should immediately update to patched versions of IBM Sterling File Gateway, as IBM has released security updates addressing this vulnerability. The implementation of comprehensive logging and monitoring systems can help detect exploitation attempts by monitoring for unusual error response patterns. Additionally, network segmentation and access controls should be enforced to limit exposure of the gateway components to untrusted networks. Security teams should conduct thorough vulnerability assessments to identify any other applications within their environment that might exhibit similar error handling weaknesses, as this vulnerability type commonly occurs in web applications where proper input validation and error sanitization practices are not consistently implemented across all components.