CVE-2004-1516 in phpWebSite
Summary
by MITRE
CRLF injection vulnerability in index.php in phpWebSite 0.9.3-4 allows remote attackers to perform HTTP Response Splitting attacks to modify expected HTML content from the server via the block_username parameter in the user module.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/30/2021
The vulnerability identified as CVE-2004-1516 represents a critical CRLF injection flaw within the phpWebSite content management system version 0.9.3-4. This security weakness specifically affects the index.php file within the user module where the block_username parameter is processed without adequate input validation or sanitization. The vulnerability enables remote attackers to exploit HTTP response splitting techniques by injecting carriage return line feed sequences into the application's response headers, thereby allowing manipulation of the server's intended HTML output. The flaw resides in the application's failure to properly escape or filter special characters that could alter the HTTP response structure, creating opportunities for attackers to inject malicious content into web responses.
This CRLF injection vulnerability operates at the HTTP protocol level where attackers can manipulate response headers by inserting CRLF sequences into the block_username parameter. When the application processes this parameter and incorporates it directly into HTTP headers without proper sanitization, it creates a condition where an attacker can inject additional headers or modify existing ones. The attack vector specifically targets the user module's index.php script, which handles authentication and user management functions, making it particularly dangerous as it can potentially allow unauthorized access or manipulation of user sessions. The vulnerability aligns with CWE-113, which describes improper neutralization of CRLF sequences in HTTP headers, and represents a classic example of how insufficient input validation can lead to serious protocol-level security issues.
The operational impact of this vulnerability extends beyond simple content modification, as it enables sophisticated attack scenarios including session hijacking, cross-site scripting exploitation, and cache poisoning attacks. Attackers can leverage this vulnerability to inject malicious headers that redirect users to phishing sites, inject malicious JavaScript code into responses, or manipulate browser behavior through header manipulation. The consequences are particularly severe in web applications that rely on proper HTTP header management for security controls such as SameSite cookies, Content Security Policy directives, or authentication tokens. This vulnerability can be exploited to bypass security mechanisms that depend on proper HTTP response formatting, potentially allowing attackers to establish persistent access to user accounts or compromise the integrity of the entire web application.
Mitigation strategies for CVE-2004-1516 should focus on implementing comprehensive input validation and sanitization measures within the phpWebSite application. Organizations should immediately apply the vendor-supplied patches or upgrade to supported versions that address this vulnerability. The recommended approach involves implementing strict validation of the block_username parameter to reject or escape CRLF sequences before processing user input. Security controls should include input filtering that removes or encodes special characters including carriage return and line feed sequences, as well as implementing proper output encoding techniques that prevent header injection attacks. Additionally, organizations should consider implementing web application firewalls that can detect and block suspicious CRLF injection patterns, and establish monitoring procedures to identify potential exploitation attempts. The remediation efforts should align with ATT&CK technique T1190, which covers exploiting vulnerabilities in web applications, and should include comprehensive testing to ensure that all input parameters are properly sanitized before being processed by the application's core functionality.