CVE-2004-2512 in DCP-Portal
Summary
by MITRE
CRLF injection vulnerability in calendar.php in DCP-Portal 5.3.2 and earlier allows remote attackers to conduct HTTP response splitting attacks to spoof web content and poison web caches via CRLF ("%0d%0a") sequences in the PHPSESSID parameter.
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Analysis
by VulDB Data Team • 07/05/2025
The CVE-2004-2512 vulnerability represents a critical cross-site scripting and response splitting flaw within the DCP-Portal content management system version 5.3.2 and earlier. This vulnerability specifically targets the calendar.php script and exploits a lack of proper input validation for the PHPSESSID parameter, which is commonly used to maintain user session state in php applications. The flaw enables remote attackers to inject carriage return line feed sequences into HTTP responses, creating a pathway for sophisticated web cache poisoning and content spoofing attacks.
The technical implementation of this vulnerability stems from the improper sanitization of user-supplied input within the session identifier parameter. When a malicious user submits a PHPSESSID value containing CRLF sequences encoded as %0d%0a, the application fails to properly escape or validate these characters before incorporating them into HTTP headers. This oversight creates an opportunity for attackers to inject additional HTTP headers into the response, effectively allowing them to manipulate the web server's response behavior and inject malicious content.
The operational impact of this vulnerability extends beyond simple content manipulation to encompass serious security implications including web cache poisoning, session hijacking, and man-in-the-middle attacks. Attackers can leverage this flaw to inject malicious content that appears legitimate to end users, potentially leading to credential theft, unauthorized access to protected resources, and compromise of user sessions. The vulnerability particularly affects web applications that rely on session management for authentication and authorization, making it a significant threat to web application security.
This vulnerability aligns with CWE-113, which describes improper neutralization of CRLF characters in HTTP headers, and maps to several ATT&CK techniques including T1190 for exploit public-facing application and T1566 for spearphishing with social engineering. The attack vector specifically targets the application layer where HTTP response manipulation occurs, making it particularly dangerous in environments where web caches are prevalent and session management is critical for application security. Organizations should implement input validation, header sanitization, and proper session management practices to mitigate this risk. The vulnerability highlights the importance of proper input validation in web applications and demonstrates how seemingly minor flaws in parameter handling can lead to significant security compromises.
Mitigation strategies should focus on implementing strict input validation for all session identifiers and HTTP headers, employing proper header sanitization techniques, and ensuring that applications properly escape special characters before incorporating user input into HTTP responses. Regular security assessments and code reviews should specifically target session management components to identify similar vulnerabilities that could enable response splitting attacks. Additionally, implementing web application firewalls and security monitoring systems can help detect and prevent exploitation attempts targeting this type of vulnerability.