CVE-2015-5211 in Spring Framework
Summary
by MITRE
Under some situations, the Spring Framework 4.2.0 to 4.2.1, 4.0.0 to 4.1.7, 3.2.0 to 3.2.14 and older unsupported versions is vulnerable to a Reflected File Download (RFD) attack. The attack involves a malicious user crafting a URL with a batch script extension that results in the response being downloaded rather than rendered and also includes some input reflected in the response.
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Analysis
by VulDB Data Team • 11/23/2024
The vulnerability identified as CVE-2015-5211 represents a critical Reflected File Download flaw within multiple versions of the Spring Framework, specifically affecting versions 3.2.0 through 3.2.14, 4.0.0 through 4.1.7, and 4.2.0 through 4.2.1. This vulnerability falls under the CWE-434 category, which specifically addresses the improper restriction of file downloads, and aligns with ATT&CK technique T1195.001 for the use of malicious file downloads in initial access phases. The flaw emerges when the framework fails to properly validate and sanitize user input that gets reflected in HTTP responses, creating an avenue for attackers to manipulate the content disposition header and file extension in HTTP responses.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious URL containing a batch script extension such as .bat or .cmd within the request parameters. When the vulnerable Spring application processes this request, it reflects the malicious input in the HTTP response without proper validation, causing the browser to interpret the response as a file download rather than HTML content rendering. This manipulation of the Content-Disposition header combined with the strategic use of file extensions allows attackers to trick users into downloading executable scripts that can perform malicious actions on the victim's system. The vulnerability is particularly dangerous because it leverages the legitimate functionality of the Spring Framework's response handling mechanisms while exploiting a lack of proper input sanitization.
The operational impact of CVE-2015-5211 extends beyond simple file download manipulation, as it can enable attackers to deliver malware payloads, execute arbitrary code, or perform phishing attacks through the downloaded scripts. Users who click on the malicious links may unknowingly download batch files that can execute commands on their systems, potentially leading to complete system compromise. The vulnerability affects organizations using older versions of Spring Framework where proper input validation and sanitization have not been implemented, making it particularly problematic for enterprises with legacy systems. The attack vector is especially concerning because it requires minimal user interaction beyond clicking a link, and the malicious nature of the downloaded files can bypass many traditional security controls.
Organizations should implement immediate mitigations including upgrading to patched versions of the Spring Framework where available, implementing strict input validation and sanitization for all user-supplied parameters, and configuring proper Content-Disposition headers to prevent automatic file downloads. Security teams should also deploy web application firewalls and implement proper output encoding to prevent reflected input from being processed as executable content. The vulnerability demonstrates the critical importance of proper input validation and the need for organizations to maintain current security patches, as the attack surface remains significant for systems running unsupported versions of the framework. Additionally, user education and awareness programs should emphasize the dangers of clicking on unexpected links, particularly in email communications or untrusted web sources.