CVE-2012-3521 in GeSHi
Summary
by MITRE
Multiple directory traversal vulnerabilities in the cssgen contrib module in GeSHi before 1.0.8.11 allow remote attackers to read arbitrary files via a .. (dot dot) in the (1) geshi-path or (2) geshi-lang-path parameter.
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Analysis
by VulDB Data Team • 03/22/2022
The vulnerability identified as CVE-2012-3521 affects the GeSHi library version 1.0.8.10 and earlier, specifically within its cssgen contrib module. This directory traversal flaw represents a critical security weakness that enables remote attackers to access arbitrary files on the server by manipulating path parameters. The vulnerability manifests through two distinct attack vectors involving the geshi-path and geshi-lang-path parameters, both of which are susceptible to manipulation using the .. (dot dot) sequence that is commonly exploited in directory traversal attacks.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the cssgen module's handling of file path parameters. When attackers supply malicious input containing .. sequences in either the geshi-path or geshi-lang-path parameters, the application fails to properly validate or sanitize these inputs before processing them. This allows the application to traverse directory structures and access files outside of the intended directory boundaries, potentially leading to unauthorized access to sensitive system files, configuration data, or other protected resources. The vulnerability directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal.
The operational impact of CVE-2012-3521 extends beyond simple file access, as it provides attackers with potential pathways to escalate privileges and execute further malicious activities within the compromised system. An attacker could potentially access configuration files containing database credentials, application secrets, or other sensitive information that could be leveraged for additional attacks. The vulnerability affects any system running GeSHi versions prior to 1.0.8.11, making it particularly concerning given the widespread use of this library for syntax highlighting in web applications. Attackers could exploit this vulnerability to retrieve system files, potentially including PHP source code, database connection details, or other sensitive artifacts that could be used to compromise the entire system.
Mitigation strategies for this vulnerability primarily involve upgrading to GeSHi version 1.0.8.11 or later, which includes proper input validation and sanitization mechanisms. System administrators should also implement proper parameter validation at multiple layers of the application architecture, including input sanitization, path validation, and access control mechanisms. The implementation of secure coding practices, such as using whitelist validation for file paths and implementing proper directory restriction mechanisms, would have prevented this vulnerability from existing in the first place. Additionally, network-level protections such as web application firewalls and intrusion detection systems can help detect and block malicious attempts to exploit this directory traversal vulnerability, though the most effective defense remains the application-level patching and proper input validation as recommended by the ATT&CK framework's defense-in-depth approach. Organizations should also conduct regular security assessments and vulnerability scanning to identify similar weaknesses in their codebase and ensure comprehensive protection against path traversal attacks.