Description
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.
References2
Metrics
- CVSS 3.1
-
4.6
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 4 · as of 14 November 2026
- CWE
- CWE-1321
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