CVE-2026-47429
Description
A flaw was found in Vitest, a testing framework. On Windows, the Vitest UI/API server incorrectly handled file serving, which could allow an attacker to read sensitive files outside the project directory. Additionally, exposed API features could be exploited to execute arbitrary scripts, leading to potential system compromise.
Statement
Vitest ships a UI and API server (enabled via the --ui or --api flags, or automatically as part of Browser Mode) that exposes file read, file write, and test-rerun functionality over HTTP. Due to an incorrect path-traversal check in the /vitest_attachment handler and related code paths, a remote attacker who can reach this server can read arbitrary files, and via the write/rerun features can achieve arbitrary code execution. Exploitation requires either exposing the server to a network host (--api.host / api.host config) or running the UI/Browser Mode on Windows.
Red Hat's shipped products use vitest exclusively as a development-time unit test runner (invoked as vitest run, test:unit, or --project in CI/build pipelines). None of the Red Hat products that ship vitest start its UI server, API server, or Browser Mode as part of their build process or shipped runtime. The @vitest/browser package (required for Browser Mode) is not present in any Red Hat product's manifest. As a result, the vulnerable code path is not reachable in any Red Hat product covered by this flaw, and affects are set to NOTAFFECTED / Vulnerable Code not in Execute Path.
Mitigation
No mitigation is required for Red Hat products, as none run Vitest's UI/API server or Browser Mode in their build or shipped runtime.
Developers who run `vitest --ui`, `vitest --api`, or Browser Mode interactively should avoid binding the server to a non-localhost host, and should upgrade to vitest >= 4.1.0 (or >= 3.2.5 on the 3.x branch), where the allowWrite/allowExec flags default to disabled whenever the server is bound to a non-localhost host.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.1 | N/A | 9.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | High | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.
Integrity
Technical Impact: Modify Files or Directories
The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.
Confidentiality
Technical Impact: Read Files or Directories
The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.
Frequently Asked Questions
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