CVE-2025-27920 in Output Messenger
Summary
by MITRE • 05/05/2025
Output Messenger before 2.0.63 was vulnerable to a directory traversal attack through improper file path handling. By using ../ sequences in parameters, attackers could access sensitive files outside the intended directory, potentially leading to configuration leakage or arbitrary file access.
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Analysis
by VulDB Data Team • 08/27/2025
The vulnerability identified as CVE-2025-27920 affects Output Messenger versions prior to 2.0.63 and represents a critical directory traversal flaw that stems from inadequate input validation and improper file path handling within the application. This weakness allows attackers to manipulate file access parameters by injecting ../ sequences into request parameters, effectively bypassing intended directory restrictions and gaining unauthorized access to files outside the application's designated file system boundaries.
The technical implementation of this vulnerability resides in the application's failure to properly sanitize user-supplied input before processing file system operations. When the application receives parameters containing directory traversal sequences, it processes these inputs without adequate validation or canonicalization, allowing attackers to navigate upward through the file system hierarchy. This flaw directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as directory traversal or path traversal attacks. The vulnerability creates a direct pathway for attackers to access sensitive system files, configuration data, and potentially user information that should remain isolated within the application's intended file access boundaries.
From an operational perspective, the impact of this vulnerability extends beyond simple unauthorized file access to encompass potential system compromise and data exfiltration. Attackers exploiting this weakness could gain access to application configuration files, database connection details, user credentials, and other sensitive information stored outside the application's intended directory structure. The consequences include potential full system compromise when combined with other vulnerabilities, as attackers might access system-level files, application binaries, or sensitive configuration data that could be used for further exploitation. This vulnerability particularly affects environments where Output Messenger is deployed with elevated privileges or where sensitive data is stored within the application's file system access paths.
Security practitioners should implement multiple layers of mitigation to address this vulnerability effectively. The primary remediation involves updating Output Messenger to version 2.0.63 or later, which includes proper input validation and canonicalization of file path parameters. Additionally, implementing proper input sanitization mechanisms that filter or reject directory traversal sequences in all user-supplied parameters represents a crucial defensive measure. Network-level protections such as web application firewalls should be configured to detect and block suspicious path traversal patterns in HTTP requests. Organizations should also conduct comprehensive security assessments of their file system access patterns and implement principle of least privilege access controls to limit the damage potential of any successful exploitation attempts. This vulnerability aligns with several ATT&CK techniques including T1059 for command and scripting interpreter and T1566 for credential access through exploitation of remote services, emphasizing the need for comprehensive defensive strategies beyond simple patching.