CVE-2026-40591 (GCVE-0-2026-40591)

Vulnerability from cvelistv5 – Published: 2026-04-21 16:54 – Updated: 2026-04-21 17:46
VLAI
Title
FreeScout: Improper Authorization in Phone Conversation Creation Enables Cross-Mailbox Hidden Customer Modification
Summary
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.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 17:46 UTC
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7712 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
freescout-help-desk freescout Affected: < 1.8.214
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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