CVE-2026-53909 (GCVE-0-2026-53909)

Vulnerability from cvelistv5 – Published: 2026-07-01 11:59 – Updated: 2026-07-01 13:37
VLAI?
Title
Arbitrary File Upload in MCO
Summary
MCO does not correctly validate types of uploaded files. File upload validation functionality relies only on client-side checks, which can be bypassed. An authorized, low-privileged attacker can upload files with arbitrary types to the server. Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.
Severity ?
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
Impacted products
Vendor Product Version
MyComplianceOffice MCO Affected: 25.3.3.1 (custom)
Create a notification for this product.
Credits
Hubert Decyusz (AFINE Team)
Show details on NVD website
To clipboard 

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  • 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.
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