CVE-2026-53903 (GCVE-0-2026-53903)

Vulnerability from cvelistv5 – Published: 2026-07-01 11:58 – Updated: 2026-07-01 13:42
VLAI?
Title
Insecure Direct Object Reference in MCO
Summary
MCO is vulnerable to an Insecure Direct Object Reference (IDOR) vulnerability in the /customer/servlet/mco/webapi/trading-document/fetchPdfStatement endpoint. The application does not properly validate whether an authenticated user is authorized to access a requested document, allowing direct retrieval based on a user-supplied identifier. An attacker can access trading documents belonging to other users by providing a valid document ID. Although exploitation requires guessing the identifier, predictable ID patterns enable feasible enumeration, leading to unauthorized disclosure of sensitive information. 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:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
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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