CVE-2004-1577 in PHP Links
Summary
by MITRE
index.php in PHP Links allows remote attackers to gain sensitive information via an invalid show parameter, which reveals the full path in an error message.
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Analysis
by VulDB Data Team • 07/16/2017
The vulnerability identified as CVE-2004-1577 affects the PHP Links application, specifically targeting the index.php script which serves as the primary entry point for the system. This flaw represents a classic information disclosure vulnerability that occurs when the application fails to properly validate user input parameters. The vulnerability manifests when an attacker submits an invalid show parameter to the index.php endpoint, causing the system to generate an error message that inadvertently exposes the full server path where the application is installed. This type of vulnerability falls under the category of improper error handling and insufficient input validation, which are fundamental security weaknesses that can provide adversaries with critical system information.
The technical implementation of this vulnerability stems from the application's lack of proper parameter validation and error handling mechanisms within the index.php script. When a user submits a malformed show parameter, the system does not sanitize or validate the input before processing it, resulting in an unhandled exception that triggers a detailed error message. This error message contains the complete file path structure, which can include sensitive information about the server environment including directory structures, potential file locations, and system configuration details. The flaw directly maps to CWE-200, which describes the exposure of sensitive information to an unauthorized actor, and CWE-123, which addresses the weakness in error handling that reveals system information.
From an operational perspective, this vulnerability poses significant risks to system security and can be exploited by attackers to gain intelligence for subsequent attacks. The disclosed full path information can be used by threat actors to understand the application's directory structure, potentially revealing other system components, file locations, and even server configurations that might be susceptible to further exploitation. The information disclosure can enable attackers to craft more targeted attacks, such as path traversal attempts or file inclusion vulnerabilities, by understanding the actual file system layout. This vulnerability aligns with ATT&CK technique T1212, which involves exploitation of system information discovery, and can contribute to broader reconnaissance activities that precede more sophisticated attacks.
The impact of this vulnerability extends beyond simple information disclosure, as it can serve as a stepping stone for attackers to conduct more advanced reconnaissance activities. The exposed server paths can reveal directory structures that might contain sensitive files, backup directories, or other system components that could be targeted for exploitation. Security professionals should recognize that this vulnerability demonstrates poor security practices in input validation and error handling, which are fundamental requirements for secure application development. The vulnerability also highlights the importance of implementing proper logging and monitoring mechanisms to detect such information disclosure attempts, as well as the necessity of configuring applications to provide generic error messages to users while logging detailed technical information internally for debugging purposes. Organizations should implement comprehensive security measures including input validation, proper error handling, and regular security assessments to prevent similar vulnerabilities from being present in their applications.