Critical severity · published Apr 21, 2026
CVE-2026-40496
FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force
9.1
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
freescout · freescout-help-desk
< 1.8.213 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40496
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40496
Patch
https://github.com/freescout-help-desk/freescout/commit/dbdf8f2260b43a21818255c70f0b61b9de9cd555
Release Notes
https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213
Exploit
https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-2783-wxmm-wmwr
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