# Office

## Description

I heard there are hidden information here, can you find it for me?

Attachment: `challenge.xlsx`

## Solution

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FnTKhz6YcVaIqHxzfgflv%2Fimage.png?alt=media&#x26;token=f32b9da1-37cf-4bdc-8610-daaeb669e396" alt=""><figcaption></figcaption></figure>

The given tab in the excel sheet does not give us any useful information. We can try to search for hidden tabs.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FeLv4UkP2v8AM4LpCLJ34%2Fimage.png?alt=media&#x26;token=514cbfb7-101e-416a-83f6-a175337d1075" alt=""><figcaption></figcaption></figure>

In `Hidden3` tab, we will see that there are hidden texts in the cells. Changing the font colour or the fill colour will not help in revealing the text.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2F9p5hRpKzxGiZl7C6GgJG%2Fimage.png?alt=media&#x26;token=e47c2af9-a09a-4143-898c-3638f2ec4b1c" alt=""><figcaption></figcaption></figure>

Therefore, we can select all cells to change the format of the cells.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FcJAi9vqZbgs5nk3ZEtV0%2Fimage.png?alt=media&#x26;token=72314449-7c6d-43ae-acf3-201dd5bdfcc0" alt=""><figcaption></figcaption></figure>

Change the format to text so that the hidden text will be visible.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FFBd4pHVrNErJUqNVYctI%2Fimage.png?alt=media&#x26;token=da7021c7-bd9a-48a0-be44-9ec225d784ae" alt=""><figcaption></figcaption></figure>

Once the hidden texts are shown, we can kind of see that it is a QR code. We can apply rules to the cells so that it will fill with colour automatically.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2F8TeMVuNnffnvph04iQZQ%2Fimage.png?alt=media&#x26;token=f2b0a162-754e-4342-a3b4-0ead22499b0e" alt=""><figcaption></figcaption></figure>

Image above shows the rules set by us to colour the cell.

<figure><img src="https://3139068166-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5otAmBnHXiDB0QXOOAMF%2Fuploads%2FL954MXAzH1ukTrsWfWMc%2Fimage.png?alt=media&#x26;token=fae78c8f-148d-42be-8450-4f7f426779ab" alt=""><figcaption></figcaption></figure>

Once the new rule is applied, a clear QR code will be shown and it will redirect us to the flag.

## Flag

`GCTF2023{F0rmatt1ng_c311s_t0_h1d3_inf0rm4t10n}`
