The discovery of a stored cross-site scripting (XSS) vulnerability within SVG file upload functionality highlights a critical, often overlooked attack vector in modern web applications. As demonstrated by a recent bug bounty find, the improper sanitization of XML-based vector graphics can lead to session hijacking and full account takeover, even when the application employs standard security controls. This article provides a comprehensive technical analysis of the SVG XSS exploitation chain, including practical payload development, bypass techniques, and mitigation strategies that are essential for both offensive and defensive security practitioners.
Learning Objectives & Secrets:
Objective 1: Understand the fundamental mechanics of SVG file parsing and identify how `
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