CVE-2026-40590

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the Change Customer modal exposes a “Create a new customer” flow via POST /customers/ajax with action=create. Under limited visibility, the endpoint drops unique-email validation. If the supplied email already belongs to a hidden customer, Customer::create() reuses that hidden customer object and fills empty profile fields from attacker-controlled input. Version 1.8.214 fixes the vulnerability.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/freescout-help-desk/freescout/commit/b3d7611e6e173ed8a5e525b791deb6b32cf1ce62
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-wjw4-8xg6-342m
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-wjw4-8xg6-342m

Configurations

No configuration.

History

No history.

Information

Published : 2026-04-21 17:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40590

Mitre link : CVE-2026-40590

CVE.ORG link : CVE-2026-40590

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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