CVE-2017-16248 in Catalyst-Plugin-Static-Simple Module
Summary
by MITRE
The Catalyst-Plugin-Static-Simple module before 0.34 for Perl allows remote attackers to read arbitrary files if there is a '.' character anywhere in the pathname, which differs from the intended policy of allowing access only when the filename itself has a '.' character.
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Analysis
by VulDB Data Team • 01/05/2023
The CVE-2017-16248 vulnerability affects the Catalyst-Plugin-Static-Simple Perl module, which is commonly used in web applications to serve static files through the Catalyst web framework. This security flaw represents a path traversal vulnerability that allows attackers to access arbitrary files on the server by manipulating the requested pathname. The vulnerability exists due to an improper validation of file paths that fails to properly restrict access to static resources, creating a significant security risk for applications that rely on this module for serving static content such as CSS files, JavaScript files, images, and other web resources.
The technical implementation of this vulnerability stems from a flawed access control mechanism within the module's file serving logic. When the module processes requests for static files, it incorrectly evaluates pathnames containing dot characters anywhere within the path structure rather than enforcing the intended restriction that only filenames with dots should be accessible. This misconfiguration allows attackers to craft malicious requests that bypass the normal access controls and traverse the file system to access files outside the intended document root or static directory. The vulnerability specifically manifests when a pathname contains a '.' character in any position, enabling attackers to exploit directory traversal patterns to access sensitive system files, configuration files, or other restricted resources that should remain protected from public access.
The operational impact of this vulnerability extends beyond simple information disclosure, as it can potentially allow attackers to access critical system files, application configuration data, database credentials, or other sensitive information stored on the server. Attackers can leverage this vulnerability to gain unauthorized access to files that may contain authentication tokens, API keys, or other confidential data that could lead to further compromise of the application or underlying system. The vulnerability affects web applications that serve static content through the Catalyst framework and can result in complete system compromise if attackers can access sensitive files such as database connection strings, application secrets, or system configuration files that contain credentials or other exploitable information.
Organizations using the affected Catalyst-Plugin-Static-Simple module should immediately upgrade to version 0.34 or later, which contains the necessary patches to address the path traversal vulnerability. The fix implements proper validation of file paths to ensure that access is only granted when the filename itself contains a dot character, rather than allowing access based on dot characters appearing anywhere within the pathname. Security teams should conduct comprehensive vulnerability assessments to identify all instances of the vulnerable module across their infrastructure and ensure proper patch management procedures are in place. Additionally, implementing proper input validation, restricting file access permissions, and monitoring for suspicious file access patterns can help mitigate the risk of exploitation. This vulnerability aligns with CWE-22 Path Traversal and relates to ATT&CK techniques involving privilege escalation and credential access through file system manipulation.