Index: /trunk/src/org/openstreetmap/josm/io/CertificateAmendment.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/io/CertificateAmendment.java	(revision 15123)
+++ /trunk/src/org/openstreetmap/josm/io/CertificateAmendment.java	(revision 15124)
@@ -184,5 +184,10 @@
                 "Taiwan_GRCA.pem",
                 "7600295eefe85b9e1fd624db76062aaaae59818a54d2774cd4c0b2c01131e1b3",
-                "https://grca.nat.gov.tw")
+                "https://grca.nat.gov.tw"),
+        // #17668 - used by city of Budapest - for https://terinfo.ujbuda.hu - https://e-szigno.hu/
+        new NativeCertAmend(Collections.singleton("Microsec e-Szigno Root CA 2009"),
+                "Microsec_e-Szigno_Root_CA_2009.pem",
+                "3c5f81fea5fab82c64bfa2eaecafcde8e077fc8620a7cae537163df36edbf378",
+                "https://e-szigno.hu"),
     };