CVE-2017-6877 in Lutim
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in SVG file handling in Lutim 0.7.1 and earlier allows remote attackers to inject arbitrary web script.
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Analysis
by VulDB Data Team • 03/14/2017
The CVE-2017-6877 vulnerability represents a critical cross-site scripting flaw discovered in Lutim version 0.7.1 and earlier, specifically within the SVG file handling component of the application. This vulnerability arises from insufficient input validation and sanitization mechanisms when processing SVG (Scalable Vector Graphics) files uploaded to the system. SVG files are inherently rich in scripting capabilities and can contain embedded JavaScript code, making them particularly dangerous when processed without proper security controls.
The technical flaw manifests when the application accepts SVG uploads and fails to properly sanitize or escape user-supplied content within these files. Attackers can craft malicious SVG files containing embedded JavaScript payloads that execute in the context of other users' browsers when the compromised file is viewed. This occurs because the application does not adequately filter or remove potentially dangerous elements such as script tags, event handlers, or data URLs that could trigger malicious code execution. The vulnerability operates at the application layer and leverages the inherent capabilities of SVG format to execute code within web browsers.
The operational impact of this vulnerability extends beyond simple data theft or session hijacking. Remote attackers can leverage this XSS flaw to perform a wide range of malicious activities including but not limited to stealing user credentials, conducting session fixation attacks, defacing web pages, or redirecting users to malicious sites. The vulnerability is particularly concerning in collaborative environments where users upload files that may be viewed by other users, as it creates a persistent threat vector that can affect multiple users simultaneously. The attack surface is broad since SVG files are commonly used for images, diagrams, and graphics in web applications, making them a frequent target for exploitation.
This vulnerability aligns with CWE-79, which specifically addresses Cross-site Scripting flaws in web applications, and represents a classic example of insufficient input sanitization. From an ATT&CK framework perspective, this vulnerability maps to T1059.007 for Scripting and T1566 for Phishing, as attackers can use this flaw to deliver malicious payloads through compromised SVG files. The remediation approach requires immediate implementation of proper input validation and output encoding mechanisms, particularly for SVG file processing. Organizations should implement strict file type validation, sanitize all SVG content by removing or escaping dangerous elements, and employ Content Security Policy (CSP) headers to mitigate potential exploitation. The vulnerability demonstrates the importance of secure file handling practices and the necessity of implementing defense-in-depth strategies to protect against file-based attacks in web applications.