CVE-2026-28736 (GCVE-0-2026-28736)

Vulnerability from cvelistv5 – Published: 2026-04-03 13:25 – Updated: 2026-04-03 14:54 Unsupported When Assigned
VLAI?
Title
Focalboard IDOR in file content endpoint allows cross-user file access (unsupported product, no fix)
Summary
** UNSUPPORTED WHEN ASSIGNED ** Focalboard version 8.0 fails to validate file ownership when serving uploaded files. This allows an authenticated attacker who knows a victim's fileID to read the content of the file. NOTE: Focalboard as a standalone product is not maintained and no fix will be issued.
Severity ?
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
Impacted products
Vendor Product Version
Mattermost Focalboard Affected: 0 , ≤ 8.0 (semver)
Create a notification for this product.
Credits
Siam Thanat Hack Company Limited
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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