Flare is a Next.js-based, self-hostable file sharing platform that integrates with screenshot tools. Prior to 1.7.3, an authenticated path traversal vulnerability in /api/avatars/[filename] allows any logged-in user to read arbitrary files from within the application container. The filename URL parameter is passed to path.join() without sanitization, and getFileStream() performs no path validation, enabling %2F-encoded ../ sequences to escape the uploads/avatars/ directory and read any file accessible to the nextjs process under /app/. Authentication is enforced by Next.js middleware. However, on instances with open registration enabled (the default), any attacker can self-register and immediately exploit this. This vulnerability is fixed in 1.7.3.
CVSS Score
6.5
EPSS Score
0.001
Published
2026-03-10
Flare is a Next.js-based, self-hostable file sharing platform that integrates with screenshot tools. Versions 1.7.0 and below allow users to upload files without proper content validation or sanitization. By embedding malicious JavaScript within an SVG (or other active content formats such as HTML or XML), an attacker can achieve script execution in the context of the application's origin when a victim views the file in “raw” mode. This results in a stored Cross-Site Scripting (XSS) vulnerability that can be exploited to exfiltrate user data. This issue has been fixed in version 1.7.1.
CVSS Score
4.6
EPSS Score
0.0
Published
2026-02-20