A prototype pollution vulnerability was found in just-extend <4.0.0 that allows attack to inject properties onto Object.prototype through its functions.
https://hackerone.com/reports/430291
Source: Mitre, NVD
Published: 2019-02-01
Updated: 2026-06-17
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
EPSS: 0.00579