CVE-2015-2028 in WebSphere eXtreme Scale
Summary
by MITRE
CRLF injection vulnerability in IBM WebSphere eXtreme Scale 7.1.0 before 7.1.0.3 and 7.1.1 before 7.1.1.1 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a crafted URL.
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Analysis
by VulDB Data Team • 03/11/2018
The CVE-2015-2028 vulnerability represents a critical CRLF injection flaw in IBM WebSphere eXtreme Scale versions 7.1.0 through 7.1.0.2 and 7.1.1 through 7.1.1.0. This vulnerability resides in the web application server component that processes HTTP requests and responses, specifically within the header validation mechanisms. The flaw enables remote attackers to inject arbitrary HTTP headers into responses by manipulating input parameters in crafted URLs, effectively bypassing the normal security boundaries that should prevent such modifications. The vulnerability is classified under CWE-1107, which specifically addresses CRLF injection in HTTP headers, making it a direct descendant of the well-known HTTP response splitting attack vector that has plagued web applications for decades.
The technical exploitation of this vulnerability occurs when the web server fails to properly sanitize user input before incorporating it into HTTP response headers. When a malicious user crafts a URL containing carriage return line feed sequences followed by HTTP headers, the vulnerable application processes these sequences without adequate validation, leading to the injection of unauthorized headers into the HTTP response. This allows attackers to manipulate the response behavior, potentially redirecting users to malicious sites, stealing session cookies, or injecting malicious content into web pages. The vulnerability stems from insufficient input validation and sanitization within the web server's header processing pipeline, creating an attack surface where user-controllable data can directly influence HTTP protocol elements.
The operational impact of CVE-2015-2028 extends beyond simple header injection, as it enables sophisticated attack vectors that can compromise entire web applications and user sessions. Attackers can leverage this vulnerability to perform HTTP response splitting attacks, where they inject multiple HTTP responses within a single HTTP transaction, allowing them to bypass security controls and manipulate web application behavior. This vulnerability particularly affects applications that rely on WebSphere eXtreme Scale for distributed caching and data management, potentially compromising the integrity of cached data and user sessions. The attack can result in session hijacking, cross-site scripting attacks, and cache poisoning, making it a significant concern for organizations that depend on IBM WebSphere for their enterprise applications. This vulnerability aligns with ATT&CK technique T1566, which covers the use of malicious headers and response manipulation in web application attacks.
Organizations should immediately implement mitigations that include input validation at multiple layers of the application stack, including the web server, application server, and application code. The most effective immediate solution involves applying the vendor-provided patches and updates that address the CRLF injection vulnerability in IBM WebSphere eXtreme Scale. Additionally, implementing web application firewalls that can detect and block CRLF sequences in HTTP headers provides an additional layer of protection. Network segmentation and monitoring for unusual header injection patterns can help detect exploitation attempts. Organizations should also consider implementing strict header validation policies, where all user-controllable input is sanitized before being used in HTTP response generation, and establish logging mechanisms that can detect potential CRLF injection attempts. The vulnerability demonstrates the critical importance of proper input validation and the principle of least privilege in web application security, where any user-controllable data should be treated as potentially malicious and validated accordingly.