Legally binding document authentication - centrally issued for every citizen

Authentic document signing in Hungary had long depended on hardware tokens, smart cards, or physical presence. The government needed a centrally managed signing infrastructure that could issue qualified electronic signatures to citizens and public administrations through existing software environments - including mobile applications - without requiring dedicated hardware. The solution had to meet strict PKI standards, comply with eIDAS, and integrate into the full range of specialised government systems.

E-Group built the Központi Dokumentumhitelesítési Ügynök (KDÜ) as a module within the Government Certificate Authority (GovCA) programme, operated by NISZ. The platform provides stored-key qualified e-signature services (KEÜSZ), timestamping (TKASZ, KEASZ, KEAESZ), and hardware security modules in private cloud. It handles the full lifecycle of authenticated, signed documents in both machine-readable and human-readable formats. Citizens and government officers can authenticate and sign documents from within their existing specialised systems - including via mobile applications - without additional hardware.

The KDÜ extended qualified e-signature capability to citizens and public administrations through standard software interfaces, removing the hardware dependency that had limited adoption. The service integrates into the broader NISZ-operated public service infrastructure alongside KAÜ, enabling authenticated document flows as a native part of government digital processes rather than a separate step.