CVE-2026-53902 (GCVE-0-2026-53902)

Vulnerability from cvelistv5 – Published: 2026-07-01 11:58 – Updated: 2026-07-01 13:42
VLAI
Title
Privilege Escalation in MCO
Summary
MCO does not properly enforce authorization checks in the /customer/servlet/mco/webapi/profile-sections/group-membership endpoint. An authenticated user can modify their group membership without proper authorization checks, allowing privilege escalation. An attacker can add themselves to arbitrary groups by supplying a valid group ID, which can be obtained via other application functionalities (e.g. /customer/servlet/mco/webapi/group/picker/groups), provided he has necessary permissions, or potentially inferred through brute-force techniques. 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
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-266 - Incorrect Privilege Assignment
  • CWE-863 - Incorrect Authorization
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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