diff --git a/core/vm/privacy/ringct.go b/core/vm/privacy/ringct.go
index cc6e3e492b5c..c9de965cea38 100644
--- a/core/vm/privacy/ringct.go
+++ b/core/vm/privacy/ringct.go
@@ -120,14 +120,15 @@ func (r Ring) Bytes() (b []byte) {
 	return
 }
 
-func PadTo32Bytes(in []byte) (out []byte) {
-	out = append(out, in...)
-	for {
-		if len(out) == 32 {
-			return
-		}
-		out = append([]byte{0}, out...)
+func PadTo32Bytes(in []byte) []byte {
+	padded := make([]byte, 32)
+	if len(in) >= 32 {
+		copy(padded, in)
+	} else {
+		copy(padded[32-len(in):], in)
 	}
+
+	return padded
 }
 
 // converts the signature to a byte array
diff --git a/core/vm/privacy/ringct_test.go b/core/vm/privacy/ringct_test.go
index 703b08df09ec..67f6c4beaf97 100644
--- a/core/vm/privacy/ringct_test.go
+++ b/core/vm/privacy/ringct_test.go
@@ -1,9 +1,12 @@
 package privacy
 
 import (
+	"bytes"
 	"fmt"
 	"testing"
-	)
+
+	"github.com/stretchr/testify/assert"
+)
 
 func TestSign(t *testing.T) {
 	/*for i := 14; i < 15; i++ {
@@ -44,3 +47,48 @@ func TestSign(t *testing.T) {
 	}
 
 }
+
+func TestPadTo32Bytes(t *testing.T) {
+	arr := [44]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34}
+
+	// test input slice is longer than 32 bytes
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[0:]), arr[0:32]), "Test PadTo32Bytes longer than 32 bytes #1")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[1:]), arr[1:33]), "Test PadTo32Bytes longer than 32 bytes #2")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[2:]), arr[2:34]), "Test PadTo32Bytes longer than 32 bytes #3")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[3:]), arr[3:35]), "Test PadTo32Bytes longer than 32 bytes #4")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[4:]), arr[4:36]), "Test PadTo32Bytes longer than 32 bytes #5")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[5:]), arr[5:37]), "Test PadTo32Bytes longer than 32 bytes #6")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[6:]), arr[6:38]), "Test PadTo32Bytes longer than 32 bytes #7")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[7:]), arr[7:39]), "Test PadTo32Bytes longer than 32 bytes #8")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[8:]), arr[8:40]), "Test PadTo32Bytes longer than 32 bytes #9")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[9:]), arr[9:41]), "Test PadTo32Bytes longer than 32 bytes #10")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:]), arr[10:42]), "Test PadTo32Bytes longer than 32 bytes #11")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[11:]), arr[11:43]), "Test PadTo32Bytes longer than 32 bytes #12")
+
+	// test input slice is equal 32 bytes
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[0:32]), arr[0:32]), "Test PadTo32Bytes equal 32 bytes #1")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[1:33]), arr[1:33]), "Test PadTo32Bytes equal 32 bytes #2")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[2:34]), arr[2:34]), "Test PadTo32Bytes equal 32 bytes #3")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[3:35]), arr[3:35]), "Test PadTo32Bytes equal 32 bytes #4")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[4:36]), arr[4:36]), "Test PadTo32Bytes equal 32 bytes #5")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[5:37]), arr[5:37]), "Test PadTo32Bytes equal 32 bytes #6")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[6:38]), arr[6:38]), "Test PadTo32Bytes equal 32 bytes #7")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[7:39]), arr[7:39]), "Test PadTo32Bytes equal 32 bytes #8")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[8:40]), arr[8:40]), "Test PadTo32Bytes equal 32 bytes #9")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[9:41]), arr[9:41]), "Test PadTo32Bytes equal 32 bytes #10")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:42]), arr[10:42]), "Test PadTo32Bytes equal 32 bytes #11")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[11:43]), arr[11:43]), "Test PadTo32Bytes equal 32 bytes #12")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[12:44]), arr[12:44]), "Test PadTo32Bytes equal 32 bytes #13")
+
+	// test input slice is shorter than 32 bytes
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:32]), arr[0:32]), "Test PadTo32Bytes shorter than 32 bytes #1")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:33]), arr[1:33]), "Test PadTo32Bytes shorter than 32 bytes #2")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:34]), arr[2:34]), "Test PadTo32Bytes shorter than 32 bytes #3")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:35]), arr[3:35]), "Test PadTo32Bytes shorter than 32 bytes #4")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:36]), arr[4:36]), "Test PadTo32Bytes shorter than 32 bytes #5")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:37]), arr[5:37]), "Test PadTo32Bytes shorter than 32 bytes #6")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:38]), arr[6:38]), "Test PadTo32Bytes shorter than 32 bytes #7")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:39]), arr[7:39]), "Test PadTo32Bytes shorter than 32 bytes #8")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:40]), arr[8:40]), "Test PadTo32Bytes shorter than 32 bytes #9")
+	assert.True(t, bytes.Equal(PadTo32Bytes(arr[10:41]), arr[9:41]), "Test PadTo32Bytes shorter than 32 bytes #10")
+}