CVE-2019-5415 in Serve
Summary
by MITRE
A bug in handling the ignore files and directories feature in serve 6.5.3 allows an attacker to read a file or list the directory that the victim has not allowed access to.
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Analysis
by VulDB Data Team • 08/04/2023
The vulnerability identified as CVE-2019-5415 resides within the serve package version 6.5.3, specifically affecting how the application processes ignore files and directories. This flaw represents a critical access control issue that undermines the security boundaries established by the application's configuration. The serve package is commonly used to serve static files and directories, often in development environments or simple web server scenarios where proper access controls are essential for maintaining data confidentiality and system integrity.
The technical implementation of this vulnerability stems from inadequate validation of file paths during the ignore file processing mechanism. When users configure ignore patterns to exclude certain files or directories from being served, the application fails to properly sanitize or validate the paths being processed. This weakness allows an attacker to craft malicious requests that bypass the intended access restrictions, enabling unauthorized reading of files or directory listing operations that should otherwise be blocked. The flaw essentially creates a path traversal condition where the ignore mechanism itself becomes a vector for privilege escalation.
From an operational perspective, this vulnerability poses significant risks to systems where serve is used to host sensitive data or where access controls are assumed to be enforced. Attackers can exploit this weakness to access configuration files, source code, database credentials, or other sensitive information that should remain protected. The impact extends beyond simple information disclosure, as it can lead to further exploitation opportunities including potential code execution or system compromise. This vulnerability particularly affects development environments where serve is commonly deployed, making it a prime target for attackers seeking to gain unauthorized access to development systems.
The vulnerability aligns with CWE-22 Path Traversal and CWE-23 Relative Path Traversal, both of which address improper handling of file paths in applications. It also maps to ATT&CK technique T1083 File and Directory Discovery, as the vulnerability enables unauthorized discovery of system files and directories. Organizations using serve package versions prior to the patched release face substantial risk, especially in environments where the application serves files from directories containing sensitive information. The exploitability of this vulnerability is heightened in scenarios where the application is configured with insufficient input validation or where default configurations might expose additional attack surfaces.
Mitigation strategies should begin with immediate patching of the serve package to version 6.5.4 or later, which addresses the specific path handling issues. Organizations should also implement additional security controls including restrictive file permissions, proper input validation, and network segmentation to limit access to affected systems. Regular security audits of development environments and application configurations are essential to identify similar vulnerabilities. The implementation of proper access control mechanisms and regular security testing can help prevent similar issues from emerging in other components of the system architecture.