CVE-2026-40590CWE-639

FreeScout's Customer AJAX Create Modifies Hidden Existing Customer

Medium · published April 21, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
24.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00325 · 24.3th percentile
Weakness
CWE-639 · Authorization Bypass Through User-Controlled Key
Published
2026-04-21T16:52Z
EPSS history
Timeline
  • 21 APR 16:52Z
    FreeScout's Customer AJAX Create Modifies Hidden Existing Customer
    cvelistv5