CVE-2026-55551
ZAC is an open-source, workflow-based Common Ground component for Dutch municipal case management
- Risk score
- 42/100
- CVSS
- 6.5 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 30 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 hasAnyApplication…
- Affected
- See advisory
- Fix
- Upgrade the product to 5.2.0 or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 6.5 medium
References
- https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f
- https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a
- https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225
- https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229
- https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0
- https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm
Original 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.
Last activity 30 Oct 2026. Patch Forecast updates every hour.