Is CVE-2026-40591 actively exploited?

No active exploitation of CVE-2026-40591 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-40591 be exploited remotely?

Yes. CVE-2026-40591 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-40591?

CVE-2026-40591 has a CVSS score of 7.1 (HIGH).

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HIGH

CVE-2026-40591

CWE-639Published: April 21, 2026· Updated: Apr 22, 2026

7.1

CVSS v3.1

EPSS:0.03%probability of exploitation in 30 daysPercentile:7.0th

Official Description

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.

NVD Source

Technical Analysis

CVE-2026-40591 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in full integrity compromise (data manipulation), with a CVSS base score of 7.1.