CVE-2026-47428CWE-79

Vitest browser mode serves unsanitized otelCarrier query parameter as inline script

Critical · published July 14, 2026

CVSS v3.1
9.6
EPSS
1%
Percentile
48.7
In the wild
Unconfirmed
What it is

Vitest is a testing framework powered by Vite. From 4.0.17 until 4.1.6 and 5.0.0-beta.3, Vitest Browser Mode served /__vitest_test__/ with the otelCarrier query parameter inserted directly into an inline module script, allowing a crafted browser-runner URL to execute arbitrary JavaScript in the Vitest server origin and recover VITEST_API_TOKEN for authenticated API calls. This issue is fixed in versions 4.1.6 and 5.0.0-beta.3.

The record
Technical detail
CVSS v3.1
9.6 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00613 · 48.7th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-07-14T19:30Z
EPSS history
Timeline
  • 14 JUL 19:30Z
    Vitest browser mode serves unsanitized otelCarrier query parameter as inline script
    cvelistv5