CVE-2018-7482 in K2 Component
Summary
by MITRE
The K2 component 2.8.0 for Joomla! has Incorrect Access Control with directory traversal, allowing an attacker to download arbitrary files, as demonstrated by a view=media&task=connector&cmd=file&target=l1_../configuration.php&download=1 request. The specific pathname ../configuration.php should be base64 encoded for a valid attack.
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Analysis
by VulDB Data Team • 08/05/2024
The vulnerability identified as CVE-2018-7482 resides within the K2 component version 2.8.0 for Joomla websites. The flaw exists in how the component processes file paths during media operations, creating an opportunity for attackers to bypass intended security restrictions and access sensitive files that should remain protected.
The technical implementation of this vulnerability stems from inadequate input validation and path sanitization within the K2 component's file handling mechanisms. When processing requests containing the media task parameters, the system fails to properly validate or sanitize the target file path specified in the request. The attack vector demonstrates a classic directory traversal exploit where the attacker crafts a malicious request with a relative path that includes ../ sequences to navigate upward through the directory structure. The specific target path ../configuration.php represents the Joomla! configuration file, which typically contains database credentials and other sensitive administrative information. The vulnerability requires base64 encoding of the target path to successfully execute the attack, indicating that the system performs some form of encoding validation or transformation during request processing.
This 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 flaw allows attackers to access files outside the intended directory scope, potentially exposing sensitive data including database configuration files, user credentials, and other system information. The operational impact extends beyond simple file retrieval, as access to the configuration.php file could enable attackers to establish persistence, escalate privileges, or use stolen credentials to compromise the entire Joomla websites running the affected K2 component version, making it particularly dangerous as it targets a widely deployed content management extension.
The attack scenario begins with an unauthenticated attacker identifying a Joomla! site using the vulnerable K2 component, followed by crafting a malicious request that leverages the directory traversal mechanism. The base64 encoding requirement suggests that the system performs some input validation that must be bypassed to achieve successful exploitation. Security implications include potential data breaches, system compromise, and unauthorized access to administrative functions. Organizations running vulnerable versions should immediately implement mitigation strategies including component updates, input validation restrictions, and network-level protections. The vulnerability also aligns with ATT&CK technique T1213.002 for credential access through web application attacks, potentially enabling further compromise through stolen administrative credentials.
Mitigation strategies should include immediate patching of the K2 component to version 2.8.1 or later, which addresses the path traversal vulnerability through proper input validation and sanitization. Network administrators should implement web application firewalls to detect and block suspicious file path traversal attempts, particularly those containing ../ sequences. Access control measures should be strengthened to limit the exposure of sensitive files, while regular security audits should verify that no other components within the Joomla! installation contain similar vulnerabilities. The vulnerability underscores the importance of proper input validation and the principle of least privilege in web application security, as well as the necessity of keeping all third-party components updated to prevent exploitation of known security flaws.