CVE-2026-53903

HIGHNVD 8.15.3▼
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 84% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 4 sources updated this week
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
8.1
EG Score
5.3(medium)
EPSS
15.9%
KEV
Not listed

Published

July 1, 2026

Last Modified

July 6, 2026

Advisory Details (2)

Auto-updated Jul 3, 2026
No patch confirmed yet.
generic

MyComplianceOffice | Compliance Management Software

https://mco.mycomplianceoffice.com/
generic

Vulnerabilities in MyComplianceOffice MCO software | CERT Polska

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

Vendor Advisories for CVE-2026-53903(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 19× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-06 18:21 UTCNVD updateCVSS v3 → 8.1 · severity → HIGH
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 14:04 UTCEG score recompute
  5. 2026-07-06 14:03 UTCGHSA enrichment
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-05 14:00 UTCEG score recompute
  9. 2026-07-05 13:59 UTCGHSA enrichment
  10. 2026-07-05 02:31 UTCEPSS rescore
  11. 2026-07-05 02:30 UTCEPSS rescore
  12. 2026-07-04 13:57 UTCEG score recompute
  13. 2026-07-04 13:56 UTCGHSA enrichment
  14. 2026-07-03 13:54 UTCEG score recompute
  15. 2026-07-03 13:54 UTCGHSA enrichment
  16. 2026-07-02 13:53 UTCEG score recompute
  17. 2026-07-02 13:53 UTCGHSA enrichment
  18. 2026-07-01 13:53 UTCEG score recompute
  19. 2026-07-01 13:52 UTCNVD updatefirst tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53903?
CVE-2026-53903 is a high vulnerability published on July 1, 2026. 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…
When was CVE-2026-53903 disclosed?
CVE-2026-53903 was first published in the National Vulnerability Database on July 1, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53903 actively exploited?
CVE-2026-53903 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 15.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53903?
CVE-2026-53903 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 5.3.
How do I remediate CVE-2026-53903?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53903, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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