Is this vulnerability remotely exploitable?

Yes, but only by authenticated users. Exploitation happens via the normal web interface or API for creating phone conversations, where a logged-in agent crafts requests with specific `customer_id` and related fields.

What level of access does an attacker need to exploit this?

The attacker must have at least a low-privileged agent account with permission to create phone conversations in one mailbox. No administrative privileges are required; the flaw stems from insufficient mailbox-scoped authorization, not from elevated roles.

What is the safest general fix pattern for this issue?

The most robust fix is to ensure all customer lookups during conversation creation are constrained by the current mailbox and user permissions. Instead of trusting client-supplied `customer_id`, the application should resolve customers only within the mailbox context associated with the authenticated session and enforce authorization checks centrally.

Severity:

HIGH RISK

(7.1)

Improper Authorization (CWE-639) in FreeScout Phone Conversation Customer Binding

CVE-2026-40591

Published:

Apr 21, 2026

Status:

Deferred

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

Recent Vulnerabilities

CWE-74;CWE-89

HIGH RISK

HIGH

(7.3)

SQL Injection via Unsanitized ID Parameter (CWE-89) in Pharmacy Sales and Inventory System /ajax.php

Database Compromise and Data Integrity Loss

April 27, 2026

CWE-863

HIGH RISK

HIGH

(8.5)

Incorrect Authorization (CWE-863) in OpenClaw chat.send Session Management

Privilege Escalation and Unauthorized Session Control

April 27, 2026

Vulnerability Type

Category:

Improper Authorization / Insecure Direct Object Reference

CWE:

CWE-639

Impact:

Unauthorized Cross-Mailbox Data Access and Customer Record Manipulation

Severity:

HIGH RISK

(7.1)

CVSS Version:

3.1

Vulnerability Type

Category:

Improper Authorization / Insecure Direct Object Reference

CWE:

CWE-639

Impact:

Unauthorized Cross-Mailbox Data Access and Customer Record Manipulation

Severity:

HIGH RISK

(7.1)

CVSS Version:

3.1

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Ask AI for summary of CodeAnt

Improper Authorization (CWE-639) in FreeScout Phone Conversation Customer Binding

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

HIGH RISK

HIGH

(7.3)

SQL Injection via Unsanitized ID Parameter (CWE-89) in Pharmacy Sales and Inventory System /ajax.php

HIGH RISK

HIGH

(8.5)

Incorrect Authorization (CWE-863) in OpenClaw chat.send Session Management

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

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