Summary
| Vulnerability Name | Arbitrary File Read via Vite WebSocket (CVE-2026-39363) |
| Released on | April 08, 2026 |
| Affected Component | Vite |
| Affected Version | 8.0.0 ≤ Vite ≤ 8.0.4 7.0.0 ≤ Vite ≤ 7.3.1 6.0.0 ≤ Vite ≤ 6.4.1 Vite ≤ 0.1.15 |
| Vulnerability Type | Arbitrary file read |
| Exploitation Condition | 1. User authentication: not required. 2. Precondition: default configurations. 3. Trigger mode: remote. |
| Impact | Exploitation difficulty: easy. Attackers can exploit this vulnerability to read arbitrary files without authorization. Severity: critical. Successful exploitation enables attackers to read arbitrary sensitive files. |
| Official Solution | Available |
About the Vulnerability
Component Introduction
Vite is a modern front-end build tool that leverages the ability to import native ES modules in browsers to enable fast development server startup and build performance. Vite aims to optimize the development experience. It uses technologies such as hot module replacement (HMR) to enable more efficient development.
Vulnerability Description
On April 08, 2026, Sangfor FarSight Labs received notification of the arbitrary file read vulnerability in Vite (CVE-2026-39363), classified as critical in threat level.
Specifically, Vite WebSocket contains an arbitrary file read vulnerability. Attackers can send the vite:invoke command over the WebSocket connection to call the fetchModule method. By crafting arbitrary file:// paths with the raw parameter, attackers can successfully bypass the access restrictions of the HTTP interface, and read any file on the server without authorization.
Affected Versions
The following Vite versions are affected:
8.0.0 ≤ Vite ≤ 8.0.4
7.0.0 ≤ Vite ≤ 7.3.1
6.0.0 ≤ Vite ≤ 6.4.1
Vite ≤ 0.1.15
Remediation Solutions
Official Solutions
The latest version has been officially released to fix the vulnerability. Affected users are advised to update Vite to the latest version.
Download link: https://github.com/vitejs/vite/releases
Temporary Solutions
- Disable unused functional modules to reduce attack entry points.
- Follow the principle of least privilege to strictly control the scope of permissions for sensitive operations.
- Do not expose services to the Internet unless necessary, to limit the access sources to trusted ranges.
- Regularly update the system and components to secure versions so that known vulnerabilities can be patched at the earliest opportunity.
Sangfor Solutions
Proactive Vulnerability Detection
The following Sangfor services can proactively detect CVE-2026-39363 vulnerabilities and quickly identify vulnerability risks in batches in business scenarios:
- Athena Managed Detection and Response (MDR): The corresponding detection solution will be released on May 30, 2026. The rule ID is SF-2026-01011.
- Athena Extended Detection and Response (XDR): The corresponding detection solution will be released on April 12, 2026. The rule ID is SF-2026-00872.
Timeline
On April 08, 2026, Sangfor FarSight Labs received notification of the arbitrary file read vulnerability in Vite (CVE-2026-39363).
On April 08, 2026, Sangfor FarSight Labs released a vulnerability alert.
Reference
https://github.com/vitejs/vite/security/advisories/GHSA-p9ff-h696-f583
Learn More
Sangfor FarSight Labs researches the latest cyber threats and unknown zero-day vulnerabilities, alerting customers to potential dangers to their organizations, and providing real-time solutions with actionable intelligence. Sangfor FarSight Labs works with other security vendors and the security community at large to identify and verify global cyber threats, providing fast and easy protection for customers.
