diff --git a/examples/nft-nd-nns/nns.go b/examples/nft-nd-nns/nns.go
index 5f67f1fba..fb21e1c1d 100644
--- a/examples/nft-nd-nns/nns.go
+++ b/examples/nft-nd-nns/nns.go
@@ -581,23 +581,47 @@ func checkIPv6(data string) bool {
 	if l < 3 || 8 < l {
 		return false
 	}
-	if fragments[0] == "2001" { // example addresses prefix
+	var hasEmpty bool
+	nums := make([]int, 8)
+	for i, f := range fragments {
+		if len(f) == 0 {
+			if i == 0 {
+				nums[i] = 0
+			} else if i == l-1 {
+				nums[7] = 0
+			} else if hasEmpty {
+				return false
+			} else {
+				hasEmpty = true
+				endIndex := 9 - l + i
+				for j := i; j < endIndex; j++ {
+					nums[j] = 0
+				}
+			}
+		} else {
+			if len(f) > 4 {
+				return false
+			}
+			n := std.Atoi(f, 16)
+			if 65535 < n {
+				panic("fragment overflows uint16: " + f)
+			}
+			idx := i
+			if hasEmpty {
+				idx = i + 8 - l
+			}
+			nums[idx] = n
+		}
+	}
+
+	f0 := nums[0]
+	if f0 < 0x2000 || f0 == 0x2002 || f0 == 0x3ffe || f0 > 0x3fff { // IPv6 Global Unicast https://www.iana.org/assignments/ipv6-address-space/ipv6-address-space.xhtml
 		return false
 	}
-	var hasEmpty bool
-	for i := 1; i < l; i++ {
-		f := fragments[i]
-		fLen := len(f)
-		if fLen == 0 {
-			if i < l-1 && hasEmpty {
-				return false
-			}
-			hasEmpty = true
-		} else {
-			if fLen > 4 {
-				return false
-			}
-			_ = std.Atoi(f, 16) // check it won't panic
+	if f0 == 0x2001 {
+		f1 := nums[1]
+		if f1 < 0x200 || f1 == 0xdb8 {
+			return false
 		}
 	}
 	return true
diff --git a/pkg/core/nonnative_name_service_test.go b/pkg/core/nonnative_name_service_test.go
index c7b4f1428..43486b2fb 100644
--- a/pkg/core/nonnative_name_service_test.go
+++ b/pkg/core/nonnative_name_service_test.go
@@ -197,7 +197,7 @@ func TestSetGetRecord(t *testing.T) {
 	testNameServiceInvoke(t, bc, nsHash, "getRecord", "1.2.3.4", "neo.com", int64(nns.A))
 	testNameServiceInvoke(t, bc, nsHash, "setRecord", stackitem.Null{}, "neo.com", int64(nns.A), "1.2.3.4")
 	testNameServiceInvoke(t, bc, nsHash, "getRecord", "1.2.3.4", "neo.com", int64(nns.A))
-	testNameServiceInvoke(t, bc, nsHash, "setRecord", stackitem.Null{}, "neo.com", int64(nns.AAAA), "2002:0000:1f1f:0000:0000:0100:11a0:addf")
+	testNameServiceInvoke(t, bc, nsHash, "setRecord", stackitem.Null{}, "neo.com", int64(nns.AAAA), "2001:0201:1f1f:0000:0000:0100:11a0:11df")
 	testNameServiceInvoke(t, bc, nsHash, "setRecord", stackitem.Null{}, "neo.com", int64(nns.CNAME), "nspcc.ru")
 	testNameServiceInvoke(t, bc, nsHash, "setRecord", stackitem.Null{}, "neo.com", int64(nns.TXT), "sometext")
 
@@ -238,30 +238,32 @@ func TestSetGetRecord(t *testing.T) {
 			{Type: nns.A, Name: "1.1", ShouldFail: true},
 			{Type: nns.A, Name: "257", ShouldFail: true},
 			{Type: nns.A, Name: "1", ShouldFail: true},
-			{Type: nns.AAAA, Name: "2001:db8::8:800:200c:417a", ShouldFail: true},
-			{Type: nns.AAAA, Name: "ff01:db8::8:800:200c:417a"},
-			{Type: nns.AAAA, Name: "ff01::101"},
-			{Type: nns.AAAA, Name: "::1"},
-			{Type: nns.AAAA, Name: "::"},
-			{Type: nns.AAAA, Name: "2001:db8:0:0:8:800:200c:417a", ShouldFail: true},
-			{Type: nns.AAAA, Name: "ff01:db8:0:0:8:800:200c:417a"},
-			{Type: nns.AAAA, Name: "ff01:0:0:0:0:0:0:101"},
-			{Type: nns.AAAA, Name: "2001:0:0:0:0:0:0:101", ShouldFail: true},
-			{Type: nns.AAAA, Name: "ff01:0:0:0:0:0:0:101"},
-			{Type: nns.AAAA, Name: "0:0:0:0:0:0:0:1"},
-			{Type: nns.AAAA, Name: "2001:0:0:0:0:0:0:1", ShouldFail: true},
-			{Type: nns.AAAA, Name: "0:0:0:0:0:0:0:0"},
-			{Type: nns.AAAA, Name: "2001:0:0:0:0:0:0:0", ShouldFail: true},
-			{Type: nns.AAAA, Name: "2001:DB8::8:800:200C:417A", ShouldFail: true},
-			{Type: nns.AAAA, Name: "FF01:DB8::8:800:200C:417A"},
-			{Type: nns.AAAA, Name: "FF01::101"},
-			{Type: nns.AAAA, Name: "fF01::101"},
-			{Type: nns.AAAA, Name: "2001:DB8:0:0:8:800:200C:417A", ShouldFail: true},
-			{Type: nns.AAAA, Name: "FF01:DB8:0:0:8:800:200C:417A"},
-			{Type: nns.AAAA, Name: "FF01:0:0:0:0:0:0:101"},
-			{Type: nns.AAAA, Name: "::ffff:1.01.1.01", ShouldFail: true},
+			// {2000} & {2001} & ]2002, 3ffe[ & {3fff} are valid values for IPv6 fragment0
+			{Type: nns.AAAA, Name: "2002:db8::8:800:200c:417a", ShouldFail: true},
+			{Type: nns.AAAA, Name: "3ffd:1b8::8:800:200c:417a"},
+			{Type: nns.AAAA, Name: "3ffd::101"},
+			{Type: nns.AAAA, Name: "2003::1"},
+			{Type: nns.AAAA, Name: "2003::"},
+			{Type: nns.AAAA, Name: "2002:db8:0:0:8:800:200c:417a", ShouldFail: true},
+			{Type: nns.AAAA, Name: "3ffd:db8:0:0:8:800:200c:417a"},
+			{Type: nns.AAAA, Name: "3ffd:0:0:0:0:0:0:101"},
+			{Type: nns.AAAA, Name: "2002:0:0:0:0:0:0:101", ShouldFail: true},
+			{Type: nns.AAAA, Name: "3ffd:0:0:0:0:0:0:101"},
+			{Type: nns.AAAA, Name: "2001:200:0:0:0:0:0:1"},
+			{Type: nns.AAAA, Name: "0:0:0:0:0:0:0:1", ShouldFail: true},
+			{Type: nns.AAAA, Name: "2002:0:0:0:0:0:0:1", ShouldFail: true},
+			{Type: nns.AAAA, Name: "2001:200:0:0:0:0:0:0"},
+			{Type: nns.AAAA, Name: "2002:0:0:0:0:0:0:0", ShouldFail: true},
+			{Type: nns.AAAA, Name: "2002:DB8::8:800:200C:417A", ShouldFail: true},
+			{Type: nns.AAAA, Name: "3FFD:1B8::8:800:200C:417A"},
+			{Type: nns.AAAA, Name: "3FFD::101"},
+			{Type: nns.AAAA, Name: "3fFD::101"},
+			{Type: nns.AAAA, Name: "2002:DB8:0:0:8:800:200C:417A", ShouldFail: true},
+			{Type: nns.AAAA, Name: "3FFD:DB8:0:0:8:800:200C:417A"},
+			{Type: nns.AAAA, Name: "3FFD:0:0:0:0:0:0:101"},
+			{Type: nns.AAAA, Name: "3FFD::ffff:1.01.1.01", ShouldFail: true},
 			{Type: nns.AAAA, Name: "2001:DB8:0:0:8:800:200C:4Z", ShouldFail: true},
-			{Type: nns.AAAA, Name: "::13.1.68.3", ShouldFail: true},
+			{Type: nns.AAAA, Name: "2001::13.1.68.3", ShouldFail: true},
 		}
 		for _, testCase := range testCases {
 			var expected interface{}