A security vulnerability has been detected in Open5GS up to 2.7.7. Affected by this issue is the function udm_nudm_uecm_handle_amf_registration_update of the file /src/udm/nudm-handler.c of the component amf-3gpp-access Endpoint. The manipulation leads to denial of service. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.