diff --git a/epan/dissectors/packet-http.c b/epan/dissectors/packet-http.c
index b481c86713..4b80bf5c92 100644
--- a/epan/dissectors/packet-http.c
+++ b/epan/dissectors/packet-http.c
@@ -3322,8 +3322,10 @@ check_auth_basic(proto_item *hdr_item, tvbuff_t *tvb, gchar *value)
 				hdr_tree = NULL;
 			value += hdrlen;
 
-			g_base64_decode_inplace(value, &len);
-			value[len] = 0;
+			if (strlen(value) > 1) {
+				g_base64_decode_inplace(value, &len);
+				value[len] = 0;
+			}
 			proto_tree_add_string(hdr_tree, hf_http_basic, tvb,
 			    0, 0, value);
 
@@ -3374,8 +3376,10 @@ check_auth_citrixbasic(proto_item *hdr_item, tvbuff_t *tvb, gchar *value, int of
 				if ( ch_ptr != NULL ) {
 					data_len = (int)(ch_ptr - value + 1);
 					data_val = wmem_strndup(wmem_packet_scope(), value, data_len);
-					g_base64_decode_inplace(data_val, &len);
-					data_val[len] = 0;
+					if (data_len > 1) {
+						g_base64_decode_inplace(data_val, &len);
+						data_val[len] = 0;
+					}
 					pi = proto_tree_add_string(hdr_tree, hf_http_citrix_user, tvb,
 					    offset , data_len - 1, data_val);
 					PROTO_ITEM_SET_GENERATED(pi);
@@ -3390,8 +3394,10 @@ check_auth_citrixbasic(proto_item *hdr_item, tvbuff_t *tvb, gchar *value, int of
 				if ( ch_ptr != NULL ) {
 					data_len = (int)(ch_ptr - value + 1);
 					data_val = wmem_strndup(wmem_packet_scope(), value, data_len);
-					g_base64_decode_inplace(data_val, &len);
-					data_val[len] = 0;
+					if (data_len > 1) {
+						g_base64_decode_inplace(data_val, &len);
+						data_val[len] = 0;
+					}
 					pi = proto_tree_add_string(hdr_tree, hf_http_citrix_domain, tvb,
 					    offset, data_len - 1, data_val);
 					PROTO_ITEM_SET_GENERATED(pi);
@@ -3406,8 +3412,10 @@ check_auth_citrixbasic(proto_item *hdr_item, tvbuff_t *tvb, gchar *value, int of
 				if ( ch_ptr != NULL ) {
 					data_len = (int)(ch_ptr - value + 1);
 					data_val = wmem_strndup(wmem_packet_scope(), value, data_len);
-					g_base64_decode_inplace(data_val, &len);
-					data_val[len] = 0;
+					if (data_len > 1) {
+						g_base64_decode_inplace(data_val, &len);
+						data_val[len] = 0;
+					}
 					pi = proto_tree_add_string(hdr_tree, hf_http_citrix_passwd, tvb,
 					    offset, data_len - 1, data_val);
 					PROTO_ITEM_SET_GENERATED(pi);
@@ -3422,8 +3430,10 @@ check_auth_citrixbasic(proto_item *hdr_item, tvbuff_t *tvb, gchar *value, int of
 				if ( ch_ptr != NULL ) {
 					data_len = (int)(ch_ptr - value + 1);
 					data_val = wmem_strndup(wmem_packet_scope(), value, data_len);
-					g_base64_decode_inplace(data_val, &len);
-					data_val[len] = 0;
+					if (data_len > 1) {
+						g_base64_decode_inplace(data_val, &len);
+						data_val[len] = 0;
+					}
 					pi = proto_tree_add_string(hdr_tree, hf_http_citrix_session, tvb,
 					    offset, data_len - 1, data_val);
 					PROTO_ITEM_SET_GENERATED(pi);
diff --git a/epan/dissectors/packet-smtp.c b/epan/dissectors/packet-smtp.c
index c45f86c3d0..08dc796004 100644
--- a/epan/dissectors/packet-smtp.c
+++ b/epan/dissectors/packet-smtp.c
@@ -309,12 +309,14 @@ decode_plain_auth(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
   gint                       length_pass;
   guint8                    *decrypt   = NULL;
   proto_item                *ti;
-  gsize                      len;
+  gsize                      len = 0;
 
   decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, a_offset, a_linelen, ENC_ASCII);
   if (smtp_auth_parameter_decoding_enabled) {
-    g_base64_decode_inplace(decrypt, &len);
-    decrypt[len] = 0;
+    if (strlen(decrypt) > 1) {
+      g_base64_decode_inplace(decrypt, &len);
+      decrypt[len] = 0;
+    }
     returncode = (gint)len;
     if (returncode) {
       length_user1 = (gint)strlen(decrypt);
@@ -557,6 +559,7 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
               ((session_state->last_auth_frame == 0) || (pinfo->num <= session_state->last_auth_frame))) {
             decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
             if ((smtp_auth_parameter_decoding_enabled) &&
+                (strlen(decrypt) > 1) &&
                 (g_base64_decode_inplace(decrypt, &decrypt_len)) &&
                 (decrypt_len > 0)) {
               decrypt[decrypt_len] = 0;
@@ -823,8 +826,12 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
             decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
             decrypt_len = linelen;
             if (smtp_auth_parameter_decoding_enabled) {
-              g_base64_decode_inplace(decrypt, &decrypt_len);
-              decrypt[decrypt_len] = 0;
+              if (strlen(decrypt) > 1) {
+                g_base64_decode_inplace(decrypt, &decrypt_len);
+                decrypt[decrypt_len] = 0;
+              } else {
+                decrypt_len = 0;
+              }
               if (decrypt_len == 0) {
                 /* Go back to the original string */
                 decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
@@ -841,8 +848,12 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
             decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
             decrypt_len = linelen;
             if (smtp_auth_parameter_decoding_enabled) {
-              g_base64_decode_inplace(decrypt, &decrypt_len);
-              decrypt[decrypt_len] = 0;
+              if (strlen(decrypt) > 1) {
+                g_base64_decode_inplace(decrypt, &decrypt_len);
+                decrypt[decrypt_len] = 0;
+              } else {
+                decrypt_len = 0;
+              }
               if (decrypt_len == 0) {
                 /* Go back to the original string */
                 decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
@@ -857,8 +868,12 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
           decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
           decrypt_len = linelen;
           if (smtp_auth_parameter_decoding_enabled) {
-            g_base64_decode_inplace(decrypt, &decrypt_len);
-            decrypt[decrypt_len] = 0;
+            if (strlen(decrypt) > 1) {
+              g_base64_decode_inplace(decrypt, &decrypt_len);
+              decrypt[decrypt_len] = 0;
+            } else {
+              decrypt_len = 0;
+            }
             if (decrypt_len == 0) {
               /* Go back to the original string */
               decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII);
@@ -906,8 +921,12 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
                  decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 11, linelen - 11, ENC_ASCII);
                  decrypt_len = linelen - 11;
                  if (smtp_auth_parameter_decoding_enabled) {
-                   g_base64_decode_inplace(decrypt, &decrypt_len);
-                   decrypt[decrypt_len] = 0;
+                   if (strlen(decrypt) > 1) {
+                     g_base64_decode_inplace(decrypt, &decrypt_len);
+                     decrypt[decrypt_len] = 0;
+                   } else {
+                     decrypt_len = 0;
+                   }
                    if (decrypt_len == 0) {
                      /* Go back to the original string */
                      decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 11, linelen - 11, ENC_ASCII);
@@ -928,8 +947,12 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
               decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 10, linelen - 10, ENC_ASCII);
               decrypt_len = linelen - 10;
               if (smtp_auth_parameter_decoding_enabled) {
-                g_base64_decode_inplace(decrypt, &decrypt_len);
-                decrypt[decrypt_len] = 0;
+                if (strlen(decrypt) > 1) {
+                  g_base64_decode_inplace(decrypt, &decrypt_len);
+                  decrypt[decrypt_len] = 0;
+                } else {
+                  decrypt_len = 0;
+                }
                 if (decrypt_len == 0) {
                   /* Go back to the original string */
                   decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 10, linelen - 10, ENC_ASCII);
@@ -1113,7 +1136,7 @@ dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_
             if (linelen >= 4) {
                 if ((smtp_auth_parameter_decoding_enabled) && (code == 334)) {
                     decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, offset + 4, linelen - 4, ENC_ASCII);
-                    if ((g_base64_decode_inplace(decrypt, &decrypt_len)) && decrypt_len > 0) {
+                    if (strlen(decrypt) > 1 && (g_base64_decode_inplace(decrypt, &decrypt_len)) && decrypt_len > 0) {
                       decrypt[decrypt_len] = 0;
                       if (g_ascii_strncasecmp(decrypt, "NTLMSSP", 7) == 0) {
                         base64_string = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 4, linelen - 4, ENC_ASCII);
diff --git a/epan/wslua/wslua_byte_array.c b/epan/wslua/wslua_byte_array.c
index bb8bb3911b..52f2983d9d 100644
--- a/epan/wslua/wslua_byte_array.c
+++ b/epan/wslua/wslua_byte_array.c
@@ -252,13 +252,15 @@ WSLUA_METHOD ByteArray_base64_decode(lua_State* L) {
     gsize len;
 
     ba2 = g_byte_array_new();
-    data = (gchar*)g_malloc(ba->len + 1);
-    memcpy(data, ba->data, ba->len);
-    data[ba->len] = '\0';
+    if (ba->len > 1) {
+        data = (gchar*)g_malloc(ba->len + 1);
+        memcpy(data, ba->data, ba->len);
+        data[ba->len] = '\0';
 
-    g_base64_decode_inplace(data, &len);
-    g_byte_array_append(ba2, data, (int)len);
-    g_free(data);
+        g_base64_decode_inplace(data, &len);
+        g_byte_array_append(ba2, data, (int)len);
+        g_free(data);
+    }
 
     pushByteArray(L,ba2);
     WSLUA_RETURN(1); /* The created `ByteArray`. */
diff --git a/ui/qt/show_packet_bytes_dialog.cpp b/ui/qt/show_packet_bytes_dialog.cpp
index 48f7bd5ac5..32147740e6 100644
--- a/ui/qt/show_packet_bytes_dialog.cpp
+++ b/ui/qt/show_packet_bytes_dialog.cpp
@@ -486,7 +486,7 @@ void ShowPacketBytesDialog::updateFieldBytes(bool initialization)
     int start = finfo_->start + start_;
     int length = end_ - start_;
     const guint8 *bytes;
-    gsize new_length;
+    gsize new_length = 0;
 
     if (!finfo_->ds_tvb)
         return;
@@ -502,7 +502,9 @@ void ShowPacketBytesDialog::updateFieldBytes(bool initialization)
     {
         bytes = tvb_get_ptr(finfo_->ds_tvb, start, -1);
         field_bytes_ = QByteArray((const char *)bytes, length);
-        g_base64_decode_inplace(field_bytes_.data(), &new_length);
+        if (field_bytes_.size() > 1) {
+            g_base64_decode_inplace(field_bytes_.data(), &new_length);
+        }
         field_bytes_.resize((int)new_length);
         break;
     }