CVE-2026-39363: Vite Affected by Arbitrary File Read via Vite Dev Server WebSocket

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-07 · updated 2026-08-25
Weakness: CWE-200

Description

Vite is a frontend tooling framework for JavaScript. From 6.0.0 to before 6.4.2, 7.3.2, and 8.0.5, if it is possible to connect to the Vite dev server’s WebSocket without an Origin header, an attacker can invoke fetchModule via the custom WebSocket event vite:invoke and combine file://... with ?raw (or ?inline) to retrieve the contents of arbitrary files on the server as a JavaScript string (e.g., export default "..."). The access control enforced in the HTTP request path (such as server.fs.allow) is not applied to this WebSocket-based execution path. This vulnerability is fixed in 6.4.2, 7.3.2, and 8.0.5.

Affected products

vitejs vite: from 6.0.0 through 6.4.1; from 7.0.0 through 7.3.1; from 8.0.0 through 8.0.4
Voidzero Vite+: through 0.1.15

References

Get alerted when CVE-2026-39363 or the next vulnerability affects your stack