What’s Vulnerable › Vulnerabilities

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

• Severity: medium (CVSS 5.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-21 · updated 2026-06-17
• Weakness: CWE-116

Description

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.

Affected products

• freescout-help-desk freescout: before 1.8.213

References

• https://github.com/freescout-help-desk/freescout/commit/9131b16f80eade81002cb9809a2603f6b61981cf
• https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213
• https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-q8v4-v62h-5528
• https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-q8v4-v62h-5528

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