High severity · published Apr 21, 2026
CVE-2026-40589
FreeScout has Customer Edit Cross-Mailbox Email Takeover
7.6
CVSS
0.2%
EPSS
No
On KEV
Description
FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, a low-privileged agent can edit a visible customer and add an email address already owned by a hidden customer in another mailbox. The server discloses the hidden customer’s name and profile URL in the success flash, reassigns the hidden email to the visible customer, and rebinds hidden-mailbox conversations for that email to the visible customer. Version 1.8.214 fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
High
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
freescout · freescout-help-desk
< 1.8.214 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40589
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40589
github.com
https://github.com/freescout-help-desk/freescout/commit/2e2fe37111d92ac665b9ad8806eac94a1a3e502c
github.com
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214
github.com
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-mv55-3mgv-fxwr
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