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+---
+slug: "2026.9.17"
+title: "2026.9.17: Security updates and ZRC duplicate-activity fix"
+---
+
+| Component   | Summary (english)                                                                                                         | Relevance for consumers (English)                                                                                                                                                                                  | Relevance for end users (Dutch)                                                                                                                                        | Relevance for system administration (Dutch) |
+| ----------- | ------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------- |
+| All modules | Fixed: security updates have been applied across all ZGW components.                                                      |                                                                                                                                                                                                                    |                                                                                                                                                                        |                                             |
+| ZRC         | Fixed: a zaakobject whose `objectIdentificatie.overigeData.activiteiten` contains two identical entries can now be saved. | Fixed: updating a zaakobject whose `objectIdentificatie.overigeData.activiteiten` contains two identical entries no longer returns a 500 error. The request is now processed and the zaakobject is stored as sent. | Opgelost: een verzoek met twee dezelfde activiteiten kon voorheen niet worden opgeslagen en leverde een onjuist zaakobject op. Zo'n verzoek wordt nu correct verwerkt. |                                             |