CVE-2024-34698: freescout Prototype Pollution — Exploit

Description

FreeScout is a free, self-hosted help desk and shared mailbox. Versions of FreeScout prior to 1.8.139 contain a Prototype Pollution vulnerability in the `/public/js/main.js` source file. The Prototype Pollution arises because the `getQueryParam` Function recursively merges an object containing user-controllable properties into an existing object (For URL Query Parameters Parsing), without first sanitizing the keys. This can allow an attacker to inject a property with a key `__proto__`, along with arbitrarily nested properties. The merge operation assigns the nested properties to the `params` object's prototype instead of the target object itself. As a result, the attacker can pollute the prototype with properties containing harmful values, which are then inherited by user-defined objects and subsequently used by the application dangerously. The vulnerability lets an attacker control properties of objects that would otherwise be inaccessible. If the application subsequently handles an attacker-controlled property in an unsafe way, this can potentially be chained with other vulnerabilities like DOM-based XSS, Open Redirection, Cookie Manipulation, Link Manipulation, HTML Injection, etc. Version 1.8.139 contains a patch for the issue.

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CVSS v3.1 Score

4.6

MEDIUM

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

Weakness Type (CWE)

CWE-1321 CWE-1321

Affected Products

Vendor	Product	Versions
freescout	freescout	< 1.8.139

References

Advisories & Patches

https://github.com/freescout-helpdesk/freescout/commit/2614514bc6d6c4ad563202a1c9cae5a97b195cc5 https://github.com/freescout-helpdesk/freescout/security/advisories/GHSA-rx6j-4c33-9h3r https://github.com/freescout-helpdesk/freescout/commit/2614514bc6d6c4ad563202a1c9cae5a97b195cc5 https://github.com/freescout-helpdesk/freescout/security/advisories/GHSA-rx6j-4c33-9h3r

Exploits

https://github.com/freescout-helpdesk/freescout/security/advisories/GHSA-rx6j-4c33-9h3r https://github.com/freescout-helpdesk/freescout/security/advisories/GHSA-rx6j-4c33-9h3r

Frequently Asked Questions

What is CVE-2024-34698? +

FreeScout is a free, self-hosted help desk and shared mailbox. Versions of FreeScout prior to 1.8.139 contain a Prototype Pollution vulnerability in the `/public/js/main.js` source file. The Prototype Pollution arises because the `getQueryParam` Function recursively merges an object containing user-controllable properties into an existing object (For URL Query Parameters Parsing), without first sanitizing the keys. This can allow an attacker to inject a property with a key `__proto__`, along with arbitrarily nested properties. The merge operation assigns the nested properties to the `params` object's prototype instead of the target object itself. As a result, the attacker can pollute the prototype with properties containing harmful values, which are then inherited by user-defined objects and subsequently used by the application dangerously. The vulnerability lets an attacker control properties of objects that would otherwise be inaccessible. If the application subsequently handles an attacker-controlled property in an unsafe way, this can potentially be chained with other vulnerabilities like DOM-based XSS, Open Redirection, Cookie Manipulation, Link Manipulation, HTML Injection, etc. Version 1.8.139 contains a patch for the issue. It has a CVSS v3.1 base score of 4.6 (MEDIUM).

How severe is CVE-2024-34698? +

CVE-2024-34698 has a CVSS v3.1 score of 4.6 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-34698? +

CVE-2024-34698 affects products from freescout, specifically: freescout. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-34698? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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