CVE-2007-2748 in PHP
Summary
by MITRE
The substr_count function in PHP 5.2.1 and earlier allows context-dependent attackers to obtain sensitive information via unspecified vectors, a different affected function than CVE-2007-1375.
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Analysis
by VulDB Data Team • 09/02/2018
The vulnerability described in CVE-2007-2748 affects the substr_count function within PHP versions 5.2.1 and earlier, representing a sensitive information disclosure issue that arises from context-dependent attack vectors. This flaw differs from CVE-2007-1375 which affected a different function within the same PHP version, indicating that multiple functions within PHP were susceptible to similar information disclosure vulnerabilities during this timeframe. The vulnerability stems from improper handling of input parameters within the substr_count function, which can lead to information leakage through memory disclosure or other indirect means. Such vulnerabilities fall under the broader category of information exposure flaws that can compromise system security and data integrity.
The technical implementation of this vulnerability involves the substr_count function's handling of string parameters and memory management during string operations. When processing certain input patterns, the function may not properly validate or sanitize its inputs, potentially causing it to leak memory contents or internal state information to attackers. This type of vulnerability typically occurs when functions do not adequately check parameter boundaries or when buffer overflows or underflows occur during string processing operations. The context-dependent nature of the vulnerability means that specific combinations of inputs or environmental conditions are required to trigger the information disclosure behavior, making it more challenging to exploit but still potentially dangerous.
The operational impact of this vulnerability extends beyond simple information disclosure, as leaked memory contents may contain sensitive data such as session identifiers, database credentials, application logic, or other confidential information that could be leveraged by attackers to escalate their privileges or compromise additional system components. Attackers could potentially use this information to craft more sophisticated attacks, bypass security controls, or gain unauthorized access to sensitive resources. The vulnerability represents a significant risk to web applications running vulnerable PHP versions, particularly those handling user input or processing sensitive data where the leaked information could be used for further exploitation. This aligns with attack patterns documented in the attack tree framework where information disclosure serves as a foundational step for more complex attack vectors.
Mitigation strategies for CVE-2007-2748 primarily involve upgrading to PHP versions 5.2.2 or later where this vulnerability has been addressed through proper input validation and memory handling improvements. System administrators should also implement proper input sanitization practices and regularly audit their applications for similar vulnerabilities in other string handling functions. Organizations should consider implementing web application firewalls and input validation controls to reduce the attack surface, while also following the principle of least privilege and maintaining up-to-date security patches across all systems. The vulnerability demonstrates the importance of comprehensive security testing and validation of all string manipulation functions, particularly in server-side scripting environments where user input processing is common. This type of vulnerability is classified under CWE-200 (Information Exposure) and may be categorized under ATT&CK techniques related to information discovery and credential access when exploited in combination with other attack vectors.