CVE-2026-39384: FreeScout Customer Merge Cross-Mailbox Authorization Bypass

Severity: high (CVSS 7.6 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: yes
Published: 2026-04-07 · updated 2026-06-17
Weakness: CWE-639

Description

FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to 1.8.212, FreeScout does not take the limit_user_customer_visibility parameter into account when merging customers. This vulnerability is fixed in 1.8.212.

Affected products

freescout-help-desk freescout: before 1.8.212 — fixed in 1.8.212

How to fix

Upgrade to a fixed version: freescout-help-desk freescout 1.8.212. Check the vendor advisory for mitigations.

References

https://github.com/freescout-help-desk/freescout/commit/b395a1179117af5e2df704c6bad71feeb301b4ce
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-j6v9-22vq-53vh
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-j6v9-22vq-53vh

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