CVE-2026-53902

Description

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 v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-266 CWE-266

CWE-863 Incorrect Authorization

Affected Products

Vendor	Product	Versions
mycomplianceoffice	mycomplianceoffice	All

References

Other References

https://cert.pl/en/posts/2026/07/CVE-2026-53902 https://mco.mycomplianceoffice.com/

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-53902? +

CVE-2026-53902 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-53902? +

CVE-2026-53902 affects products from mycomplianceoffice, specifically: mycomplianceoffice. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-53902? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2024-56513

Karmada is a Kubernetes management system that allows users to run cloud-native applications across multiple Kubernetes clusters and clouds. Prior …

CVE-2025-26523

This vulnerability exists in RupeeWeb trading platform due to insufficient authorization controls on certain API endpoints handling addition and deletion …

CVE-2025-0131

An incorrect privilege management vulnerability in the OPSWAT MetaDefender Endpoint Security SDK used by the Palo Alto Networks GlobalProtect™ app …

CVE-2025-48741

A Broken Access Control vulnerability in StrangeBee TheHive 5.2.0 before 5.2.16, 5.3.0 before 5.3.11, and 5.4.0 before 5.4.10 allows remote, …

CVE-2025-4228

An incorrect privilege assignment vulnerability in Palo Alto Networks Cortex® XDR Broker VM allows an authenticated administrative user to execute …

CVE-2025-0139

An incorrect privilege assignment vulnerability in Palo Alto Networks Autonomous Digital Experience Manager allows a locally authenticated low privileged user …