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CVE-2026-40496 (GCVE-0-2026-40496)

Vulnerability from cvelistv5 – Published: 2026-04-21 01:38 – Updated: 2026-04-21 13:50
VLAI
Title
FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force
Summary
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.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 13:50 UTC
CWE
  • CWE-330 - Use of Insufficiently Random Values
  • CWE-340 - Generation of Predictable Numbers or Identifiers
Assigner
References
Impacted products
Vendor Product Version CPE status
freescout-help-desk freescout Affected: < 1.8.213
guessed Create a notification for this product.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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