CVE-2018-6881 in EmpireCMS
Summary
by MITRE
EmpireCMS 6.6 allows remote attackers to discover the full path via an array value for a parameter to admin/tool/ShowPic.php.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/04/2020
EmpireCMS version 6.6 contains a critical path disclosure vulnerability that enables remote attackers to obtain the complete server path through manipulation of parameter values in the admin/tool/ShowPic.php script. This vulnerability arises from insufficient input validation and improper error handling within the administrative tool component, specifically when processing array parameters that are not properly sanitized before being used in file system operations. The flaw exists in the way the application processes user-supplied data without adequate sanitization measures, allowing attackers to inject array structures that trigger unintended path exposure during image processing operations.
The technical implementation of this vulnerability stems from CWE-200, which addresses improper exposure of sensitive information, and CWE-470, which covers unsafe use of the eval() function. The ShowPic.php script fails to properly validate or sanitize array inputs, creating a path traversal scenario where attacker-controlled data flows directly into system path resolution functions. When an attacker submits an array parameter to the script, the application processes this data without proper boundary checks, resulting in the exposure of the absolute file system path where EmpireCMS is installed. This information disclosure represents a significant security risk as it provides attackers with critical system information that can be leveraged for further exploitation.
The operational impact of this vulnerability extends beyond simple information disclosure, as it creates a foundation for more sophisticated attacks within the ATT&CK framework under the T1059.001 technique for command and scripting interpreter. With knowledge of the server path structure, attackers can better plan subsequent exploitation attempts including local file inclusion vulnerabilities, directory traversal attacks, or even privilege escalation within the application's administrative interface. The exposure of the installation path also aids in fingerprinting the target system, allowing attackers to identify specific versions and potentially discover other vulnerabilities associated with EmpireCMS 6.6. This path disclosure can be particularly dangerous in environments where multiple applications share the same server infrastructure, as it may reveal the presence of additional vulnerable components.
Security mitigations for this vulnerability should focus on implementing comprehensive input validation and sanitization procedures within the admin/tool/ShowPic.php script. The application must validate all incoming parameters to ensure they conform to expected data types and formats, rejecting any array inputs that are not explicitly required for legitimate functionality. Input sanitization should include proper escaping of special characters and implementation of strict type checking to prevent array injection attacks. Additionally, the application should implement proper error handling that does not expose internal system paths or file locations to end users. Organizations should also consider implementing web application firewalls with rules specifically designed to detect and block suspicious parameter patterns, as well as regular security audits of administrative components to identify similar vulnerabilities. The fix should align with OWASP Top Ten security principles by ensuring proper input validation and output encoding to prevent information disclosure vulnerabilities.