{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53903","assignerOrgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","state":"PUBLISHED","assignerShortName":"CERT-PL","dateReserved":"2026-06-11T07:44:52.179Z","datePublished":"2026-07-01T11:58:36.922Z","dateUpdated":"2026-07-01T13:42:31.836Z"},"containers":{"cna":{"providerMetadata":{"orgId":"4bb8329e-dd38-46c1-aafb-9bf32bcb93c6","shortName":"CERT-PL","dateUpdated":"2026-07-01T11:58:36.922Z"},"title":"Insecure Direct Object Reference in MCO","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-639","description":"CWE-639 Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"affected":[{"vendor":"MyComplianceOffice","product":"MCO","versions":[{"status":"affected","version":"25.3.3.1","versionType":"custom"}],"defaultStatus":"unknown"}],"descriptions":[{"lang":"en","value":"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.\nAn 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.\n\nBecause vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1 but may also affect other versions.","supportingMedia":[{"type":"text/html","base64":false,"value":"MCO is vulnerable to an Insecure Direct Object Reference (IDOR) vulnerability in the <i>/customer/servlet/mco/webapi/trading-document/fetchPdfStatement</i> 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.<br>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.<br><br>Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 25.3.3.1&nbsp;but may also affect other versions."}]}],"references":[{"url":"https://cert.pl/en/posts/2026/07/CVE-2026-53902","tags":["third-party-advisory"]},{"url":"https://mco.mycomplianceoffice.com/","tags":["product"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":5.3,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"}}],"credits":[{"lang":"en","value":"Hubert Decyusz (AFINE Team)","type":"finder"}],"source":{"discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-01T13:42:26.696418Z","id":"CVE-2026-53903","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-01T13:42:31.836Z"}}]}}