CVE-2018-16181 in i-filter
Summary
by MITRE
HTTP header injection vulnerability in i-FILTER Ver.9.50R05 and earlier may allow remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks that may result in an arbitrary script injection or setting an arbitrary cookie values via unspecified vectors.
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Analysis
by VulDB Data Team • 04/27/2020
The HTTP header injection vulnerability identified as CVE-2018-16181 affects i-FILTER version 9.50R05 and earlier implementations, representing a critical security flaw that undermines the integrity of web application communications. This vulnerability resides within the application's handling of HTTP headers, specifically in how it processes user-supplied input that flows into HTTP response headers without adequate sanitization or validation mechanisms. The flaw enables attackers to inject malicious HTTP headers into responses generated by the application, creating a pathway for sophisticated attack vectors that can compromise the security posture of affected systems.
The technical exploitation of this vulnerability stems from insufficient input validation and sanitization practices within the i-FILTER application's HTTP response generation process. Attackers can leverage this weakness through unspecified vectors to inject arbitrary HTTP headers, which can then be used to manipulate the behavior of web browsers and intermediate proxies. The vulnerability directly maps to CWE-113, which describes improper neutralization of CRLF characters in HTTP headers, a common pattern that allows attackers to inject malicious content into HTTP responses. This specific weakness creates conditions where attackers can perform HTTP response splitting attacks, a technique that exploits the way web servers and browsers process multiple HTTP headers.
The operational impact of this vulnerability extends beyond simple header injection, as it enables sophisticated attack scenarios including arbitrary script injection and unauthorized cookie manipulation. When attackers successfully inject HTTP headers, they can potentially redirect users to malicious sites, inject malicious JavaScript code into web pages, or manipulate session cookies to hijack user sessions. The ability to set arbitrary cookie values creates additional attack surface for session management bypasses and cross-site scripting exploits. This vulnerability particularly affects web applications that rely on i-FILTER for content filtering or security enforcement, potentially compromising the security of entire network infrastructures that depend on the application's proper functioning.
Organizations affected by this vulnerability should prioritize immediate remediation through patching to the latest available version of i-FILTER that addresses the HTTP header injection flaw. The remediation process should include comprehensive testing of the patched environment to ensure that the vulnerability has been fully resolved and that no regressions have been introduced. Security teams should also implement additional monitoring mechanisms to detect potential exploitation attempts and establish network-level controls to prevent unauthorized header injection attempts. According to ATT&CK framework, this vulnerability aligns with techniques such as T1071.004 for application layer protocol and T1566 for credential access through social engineering, as attackers may use the injected headers to redirect users to malicious sites or manipulate session cookies for unauthorized access. Organizations should also consider implementing web application firewalls and input validation controls to provide additional defense-in-depth measures against similar vulnerabilities in other applications within their infrastructure.