Vulnerability Description
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to 1.8.220, the email processing pipeline in FreeScout's FetchEmails command has two code paths for identifying agent (user) replies based on In-Reply-To / References headers. The notification reply path (notify-{thread_id}-{user_id}-...) extracts thread_id and user_id directly from the Message-ID without HMAC verification. An external attacker who can spoof the From address of a helpdesk agent can inject messages that FreeScout processes as legitimate agent replies — which are then automatically forwarded to customers via the legitimate SMTP server. This vulnerability is fixed in 1.8.220.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/freescout-help-desk/freescout/commit/d902f19038213c6a376947d2
- https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-6r38-6
- https://vincent.vulcoord.net/score/?state=Not+Scored&year=2026&year=2025&assigne
FAQ
What is CVE-2026-47123?
CVE-2026-47123 is a vulnerability with a CVSS score of 7.5 (HIGH). FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to 1.8.220, the email processing pipeline in FreeScout's FetchEmails command has two code paths for identifying...
How severe is CVE-2026-47123?
CVE-2026-47123 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-47123?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.