🛡️ CVE-2026-53903 — mycomplianceoffice

🟠 CVSS 8.1 — High ✅ No Known Exploit CWE-639 NVD
8.1
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

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.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability none.

Weakness class

CVE-2026-53903 is classified as CWE-639: Authorization Bypass Through User-Controlled Key. An object is selected by an identifier from the request without checking the caller owns it.

Affected software

CVE-2026-53903 is recorded against 1 package.

  • mycomplianceoffice

Timeline and source

Published on 1 July 2026 and last revised on 6 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

cert.pl
mco.mycomplianceoffice.com

Details

Severity HIGH
CVSS Score 8.1
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CWE CWE-639
Public Exploit ✅ No
Source NVD
Published 2026-07-01
Updated 2026-08-11
Modified 2026-07-06
Fix URL N/A

Affected Packages

Software From version Fixed in
mycomplianceoffice — —

Similar Threats

Site Security Check

Is mycomplianceoffice part of your stack?

CVE-2026-53903 is rated CVSS 8.1 High. BotEraser scans your installation against known CVE records and tells you whether this vulnerability applies to the versions you actually run.

Scan My Site Free →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.