CVE-2026-55551
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.
Executive briefing
The source record describes: 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. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Limited Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
CWE-285CWE-639Affected products and versions
NVD has not supplied machine-readable vulnerable CPE product/version entries for this CVE. This is an information gap, not proof that no products are affected. Check the vendor advisory references below.
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225 VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229 VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0 VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm VENDOR security-advisories@github.com
- https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm VENDOR 134c704f-9b21-4f2e-91b3-4a467353bcc0
Information gaps & confidence notes
These gaps indicate missing source data. CVE Watch does not fill them with guessed product, exploit or patch details.
- NVD does not currently provide machine-readable vulnerable CPE product/version entries for this record.
Last enrichment: 2026-11-07T17:15:22+00:00 · Source last modified: 2026-11-06T17:18:29.563