CVE-2026-40567 MEDIUM

CVE-2026-40567: FreeScout has HTML Injection in Outgoing Emails via Unsanitized Customer Name in Signature Variables

Vendor Freescout-Help-Desk
Product freescout
Weakness CWE-116
Published April 21, 2026
Last update April 21, 2026

CVSS base score

5.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, an unauthenticated attacker can inject arbitrary HTML into outgoing emails generated by FreeScout by sending an email with a crafted From display name. The name is stored in the database without sanitization and rendered unescaped into outgoing reply emails via the `{%customer.fullName%}` signature variable. This allows embedding phishing links, tracking pixels, and spoofed content inside legitimate support emails sent from the organization's address. Version 1.8.213 fixes the issue.

Key dates

02Disclosure timeline

April 21, 2026 CVE published
April 21, 2026 Record updated