Junglewise Threat Intelligence

CVE-2026-39363: Vite arbitrary file read via dev server WebSocket

CVE-2026-39363 · Severity: high · CVSS 7.5 · Published 2026-04-07

Technologies: Vite. Vendors: Vite, Red Hat.

Executive brief

Vite is a popular development tool used by software engineers to build and test web applications. A security flaw in its development server allows unauthorized users to bypass security restrictions and read sensitive files from the developer's computer or build environment. This could lead to the exposure of source code, configuration files, or credentials if the development server is exposed to a network.

Technical details

An information disclosure vulnerability exists in the Vite development server due to insufficient access control enforcement on the WebSocket execution path. While the HTTP request path correctly enforces 'server.fs.allow' restrictions, the 'fetchModule' method exposed via the 'vite:invoke' WebSocket event does not. An attacker can connect to the WebSocket without an Origin header and use 'file://' URIs combined with the '?raw' or '?inline' query parameters to retrieve arbitrary local files as JavaScript strings. This exploit requires the Vite dev server to be bound to a network-accessible interface (e.g., via --host) and for the WebSocket server to be enabled.

Affected products

  • Vite Vite >=6.0.0, <6.4.2; >=7.0.0, <7.3.2; >=8.0.0, <8.0.5
  • Vite vite-plus <=0.1.15
  • Red Hat Ansible Automation Platform 2.5, 2.6

Timeline

  • 2026-04-06: advisory: GitHub Security Advisory published by Vite maintainers
  • 2026-04-07: disclosed: NVD publication date
  • 2026-06-09: patched: Red Hat released security updates for Ansible Automation Platform

References

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