{"id":"CVE-2026-55551","state":"PUBLISHED","title":"ZAC: Missing per-zaaktype authorization on by-ID decision and process reads","description":"ZAC is an open-source, workflow-based Common Ground component for Dutch municipal case management. Prior to 5.2.0, by-id read endpoints in `src/main/kotlin/nl/info/zac/app/zaak/ZaakRestService.kt` omit `assertPolicy`(`policyService.readZaakRechten(zaak).lezen`) authorization. `RequestAuthorizationFilter` and `hasAnyApplicationRole` require only an application role on any zaaktype, not the target case's type, while `zaak-rechten.rego` enforces the actual `zaaktype_allowed` boundary only when invoked. An authenticated low-privileged municipal user who knows a case or decision UUID can use `GET /rest/zaken/besluit/zaakUuid/{uuid}` (`listBesluitenForZaakUUID`) to read decisions including types, dates, and free-text toelichting; `GET /rest/zaken/besluit/{uuid}/historie` (`listBesluitHistorie`) to read audit old/new values; and `GET /rest/zaken/{uuid}/process-diagram` (`downloadProcessDiagram`) to read BPMN workflow state across unauthorized zaaktypes. The advisory also identifies `zaak/{uuid}/afzender` (`listAfzendersVoorZaak`) as exposing zaaktype mailbox configuration without a policy check. The search/_zoek path is correctly authorization-filtered and is not part of this by-id read cluster. This issue is fixed in version 5.2.0.","publishedAt":"2026-10-30T16:48:51.352Z","updatedAt":"2026-10-30T16:48:51.352Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["infonl dimpact-zaakafhandelcomponent"],"affected":[{"vendor":"infonl","product":"dimpact-zaakafhandelcomponent","versions":[{"version":"< 5.2.0","status":"affected"}]}],"references":["https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm","https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225","https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229","https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f","https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a","https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0"],"weaknesses":["CWE-285","CWE-639"],"ingestedAt":"2026-10-30T16:54:06.455Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55551.json","commit":"48122c4b3bcd05d954afe8acd0951f0fe166e5af","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55551","state":"PUBLISHED","datePublished":"2026-10-30T16:48:51.352Z","dateUpdated":"2026-10-30T16:48:51.352Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-16T23:01:04.075Z"},"containers":{"cna":{"title":"ZAC: Missing per-zaaktype authorization on by-ID decision and process reads","descriptions":[{"lang":"en","value":"ZAC is an open-source, workflow-based Common Ground component for Dutch municipal case management. Prior to 5.2.0, by-id read endpoints in `src/main/kotlin/nl/info/zac/app/zaak/ZaakRestService.kt` omit `assertPolicy`(`policyService.readZaakRechten(zaak).lezen`) authorization. `RequestAuthorizationFilter` and `hasAnyApplicationRole` require only an application role on any zaaktype, not the target case's type, while `zaak-rechten.rego` enforces the actual `zaaktype_allowed` boundary only when invoked. An authenticated low-privileged municipal user who knows a case or decision UUID can use `GET /rest/zaken/besluit/zaakUuid/{uuid}` (`listBesluitenForZaakUUID`) to read decisions including types, dates, and free-text toelichting; `GET /rest/zaken/besluit/{uuid}/historie` (`listBesluitHistorie`) to read audit old/new values; and `GET /rest/zaken/{uuid}/process-diagram` (`downloadProcessDiagram`) to read BPMN workflow state across unauthorized zaaktypes. The advisory also identifies `zaak/{uuid}/afzender` (`listAfzendersVoorZaak`) as exposing zaaktype mailbox configuration without a policy check. The search/_zoek path is correctly authorization-filtered and is not part of this by-id read cluster. This issue is fixed in version 5.2.0."}],"affected":[{"vendor":"infonl","product":"dimpact-zaakafhandelcomponent","versions":[{"version":"< 5.2.0","status":"affected"}]}],"references":[{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225","tags":["x_refsource_MISC"]},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229","tags":["x_refsource_MISC"]},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f","tags":["x_refsource_MISC"]},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a","tags":["x_refsource_MISC"]},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0","name":"https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-285","lang":"en","description":"CWE-285: Improper Authorization","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-30T16:48:51.352Z"},"source":{"advisory":"GHSA-cv9m-35q4-cxfm","discovery":"UNKNOWN"}}}}}