CVE-2026-40591: high-severity vulnerability in freescout-help-desk freescout
FreeScout: Improper Authorization in Phone Conversation Creation Enables Cross-Mailbox Hidden Customer Modification
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.2%
FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the phone-conversation creation flow accepts attacker-controlled `customer_id`, `name`, `to_email`, and `phone` values and resolves the target customer in the backend without enforcing mailbox-scoped customer visibility. As a result, a low-privileged agent who can create a phone conversation in Mailbox A can bind the new Mailbox A phone conversation to a hidden customer from Mailbox B and add a new alias email to that hidden customer record by supplying `to_email`. Version 1.8.214 fixes the vulnerability.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Affected products
freescout-help-desk · freescoutRelated CVEs — freescout-help-desk freescout
In the same product, most dangerous first.
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