CVE-2026-40496

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/freescout-help-desk/freescout/commit/dbdf8f2260b43a21818255c70f0b61b9de9cd555	Patch
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213	Release Notes
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-2783-wxmm-wmwr	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freescout:freescout:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-21 02:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40496

Mitre link : CVE-2026-40496

CVE.ORG link : CVE-2026-40496

JSON object : View

Products Affected

freescout

freescout

CWE

CWE-330

Use of Insufficiently Random Values

CWE-340

Generation of Predictable Numbers or Identifiers

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