CVE-2026-40590: CWE-639: Authorization Bypass Through User-Controlled Key in freescout-help-desk freescout
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.
AI Analysis
Technical Summary
CVE-2026-40590 is an authorization bypass vulnerability in FreeScout (a self-hosted help desk software) versions before 1.8.214. The vulnerability arises because the 'Create a new customer' flow via POST /customers/ajax?action=create drops unique-email validation when the email belongs to a hidden customer. This allows an attacker with limited privileges to reuse a hidden customer object and update empty profile fields with attacker-controlled input. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key).
Potential Impact
The vulnerability allows an attacker with limited privileges to bypass authorization controls and modify profile information of hidden customers by exploiting the lack of unique-email validation. This can lead to unauthorized data manipulation but does not directly impact confidentiality or availability. The CVSS score is 4.3 (medium severity), indicating limited impact primarily on integrity.
Mitigation Recommendations
Upgrade FreeScout to version 1.8.214 or later, where this vulnerability is fixed. Since no official patch link or advisory is provided, users should verify the version and apply the update accordingly. Patch status is not explicitly confirmed beyond the version fix note, so check vendor sources for the latest remediation guidance.
CVE-2026-40590: CWE-639: Authorization Bypass Through User-Controlled Key in freescout-help-desk freescout
Description
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40590 is an authorization bypass vulnerability in FreeScout (a self-hosted help desk software) versions before 1.8.214. The vulnerability arises because the 'Create a new customer' flow via POST /customers/ajax?action=create drops unique-email validation when the email belongs to a hidden customer. This allows an attacker with limited privileges to reuse a hidden customer object and update empty profile fields with attacker-controlled input. The vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key).
Potential Impact
The vulnerability allows an attacker with limited privileges to bypass authorization controls and modify profile information of hidden customers by exploiting the lack of unique-email validation. This can lead to unauthorized data manipulation but does not directly impact confidentiality or availability. The CVSS score is 4.3 (medium severity), indicating limited impact primarily on integrity.
Mitigation Recommendations
Upgrade FreeScout to version 1.8.214 or later, where this vulnerability is fixed. Since no official patch link or advisory is provided, users should verify the version and apply the update accordingly. Patch status is not explicitly confirmed beyond the version fix note, so check vendor sources for the latest remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-14T14:07:59.641Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e7b0e619fe3cd2cde9a4c2
Added to database: 4/21/2026, 5:16:22 PM
Last enriched: 4/21/2026, 5:32:13 PM
Last updated: 4/22/2026, 6:10:46 AM
Views: 12
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