CVE-2026-53592 MEDIUM

CVE-2026-53592: FreeScout vulnerable to prototype pollution in getQueryParam

Vendor Freescout-Help-Desk
Product freescout
Weakness CWE-1321
Published July 20, 2026
Last update July 20, 2026

CVSS base score

4.6/10
Attack vector Network
Attack complexity High
Privileges required Low
User interaction Required
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L

What the vulnerability does

01Description

FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. A Prototype Pollution condition in the `getQueryParam` function `/public/js/main.js` and was addressed in version 1.8.139 by blocking URL query keys matching the pattern `__proto__`. However, this mitigation is incomplete: it only filters top-level `__proto__` keys and fails to sanitize nested forms such as `b[__proto__][polluted]=PWNED`. As a result, an attacker-controlled URL query string can still write into `Object.prototype` on any page that loads `main.js`. Version 1.8.223 contains a updated fix.

Key dates

02Disclosure timeline

July 20, 2026 CVE published