CVE-2026-53902

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cert.pl/en/posts/2026/07/CVE-2026-53902	Third Party Advisory
https://mco.mycomplianceoffice.com/	Product

Configurations

Configuration 1 (hide)

cpe:2.3:a:mycomplianceoffice:mycomplianceoffice:25.3.3.1:*:*:*:*:*:*:*

History

06 Jul 2026, 17:39

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.5
First Time		Mycomplianceoffice mycomplianceoffice Mycomplianceoffice
CPE		cpe:2.3:a:mycomplianceoffice:mycomplianceoffice:25.3.3.1:::::::*
References	~~() https://cert.pl/en/posts/2026/07/CVE-2026-53902 -~~	() https://cert.pl/en/posts/2026/07/CVE-2026-53902 - Third Party Advisory
References	~~() https://mco.mycomplianceoffice.com/ -~~	() https://mco.mycomplianceoffice.com/ - Product

01 Jul 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-01 13:17

Updated : 2026-07-06 17:39

NVD link : CVE-2026-53902

Mitre link : CVE-2026-53902

CVE.ORG link : CVE-2026-53902

JSON object : View

Products Affected

mycomplianceoffice

mycomplianceoffice

CWE

CWE-266

Incorrect Privilege Assignment

CWE-863

Incorrect Authorization

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