CVE-2026-30942: Flare has a Path Traversal in /api/avatars/[filename]

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-10 · updated 2026-06-17
Weakness: CWE-22

Description

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.

Affected products

FlintSH Flare: before 1.7.3 — fixed in 1.7.3

How to fix

Upgrade to a fixed version: FlintSH Flare 1.7.3. Check the vendor advisory for mitigations.

References

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