CVE-2013-1647 in Server
Summary
by MITRE
Multiple CRLF injection vulnerabilities in Open-Xchange Server before 6.20.7 rev14, 6.22.0 before rev13, and 6.22.1 before rev14 allow remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a crafted parameter, as demonstrated by (1) the location parameter to ajax/redirect or (2) multiple infostore URIs.
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Analysis
by VulDB Data Team • 10/25/2024
The CVE-2013-1647 vulnerability represents a critical class of security flaws in the Open-Xchange Server platform that exposes organizations to sophisticated header injection attacks. This vulnerability specifically targets the server's handling of user-supplied input within HTTP header fields, creating opportunities for attackers to manipulate server responses and potentially execute malicious actions. The affected versions span multiple release branches including 6.20.7 rev14, 6.22.0 rev13, and 6.22.1 rev14, indicating a widespread issue that affected a significant portion of the Open-Xchange user base during that period. The vulnerability manifests through CRLF (Carriage Return Line Feed) injection techniques that exploit improper input validation mechanisms within the server's HTTP response handling code.
The technical implementation of this vulnerability stems from inadequate sanitization of user-controllable parameters before they are incorporated into HTTP headers. Attackers can craft malicious input containing CRLF sequences that, when processed by the vulnerable server, result in the injection of arbitrary HTTP headers into the server's response. The vulnerability is particularly dangerous because it allows for HTTP response splitting attacks, where an attacker can inject multiple HTTP responses into a single HTTP transaction, potentially enabling session hijacking, cross-site scripting attacks, or cache poisoning. The attack vectors identified in the vulnerability description include the location parameter within the ajax/redirect endpoint and multiple infostore URIs, both of which represent legitimate server functionality that can be abused when proper input validation is absent.
The operational impact of CVE-2013-1647 extends beyond simple header injection, as it creates a foundation for more complex attack scenarios that can compromise user sessions and application integrity. When successful, these attacks can lead to unauthorized access to user accounts, data exfiltration, and the ability to manipulate application behavior through injected headers. The vulnerability's presence in multiple versions of the Open-Xchange Server indicates a fundamental flaw in the input validation architecture that was not properly addressed across the product's release lifecycle. Organizations using affected versions faced significant risk of exploitation, particularly in environments where the server handled sensitive user data or authenticated transactions. The vulnerability aligns with CWE-113, which specifically addresses improper neutralization of CRLF sequences in HTTP headers, and represents a clear violation of secure coding practices that should prevent such injection attacks.
Mitigation strategies for CVE-2013-1647 require immediate implementation of input validation and sanitization measures across all user-controllable parameters that are used in HTTP header construction. Organizations should implement strict validation of all input parameters, particularly those that are directly incorporated into HTTP headers, using allow-list approaches that reject any input containing CRLF sequences or other potentially dangerous characters. The recommended solution involves upgrading to patched versions of the Open-Xchange Server, specifically versions 6.20.7 rev14, 6.22.0 rev13, and 6.22.1 rev14, which contain the necessary fixes to prevent CRLF injection. Additionally, implementing web application firewalls with content inspection capabilities can provide an additional layer of protection, while monitoring for unusual HTTP header patterns can help detect potential exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to T1071.004 for Application Layer Protocol: DNS and T1566 for Phishing, as attackers can leverage the header injection to redirect users to malicious sites or manipulate session handling mechanisms. Security teams should also consider implementing proper HTTP header configuration to prevent the server from processing injected headers, and establish monitoring procedures to detect unusual patterns in HTTP response construction that might indicate exploitation attempts.