Auth bypass in Vitejs Vite
CVE-2026-39363
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.
Vulnerability class: Information Disclosure
EPSS: 0.034 (88.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Vitejs Vite — versions >= 8.0.0, < 8.0.5, >= 7.0.0, < 7.3.2, >= 6.0.0, < 6.4.2
- Vitejs Vite-plus — versions < 0.1.16
- Voidzero Vite\+
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-39363?
- CVE-2026-39363 is a high-severity vulnerability in Vitejs Vite, classified under Information Disclosure. CVSS score: 7.5/10. Published 2026-04-07.
- How severe is CVE-2026-39363?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2026-39363 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.