HONG-YI.ME

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WhiteHacks CTF Writeup - Age Unknown

b

Category

OSINT

Flag

WH2021{DDMMYYYY}

Steps

Read the description. It reads:

So, it's my friend's birthday soon and I want to surprise him. His name is Andrew Yeoh Boon How and I heard he's quite active on Twitter. Can you help me find out when his birthday is?

Filter keywords out. They are:

So, it's my friend's birthday soon and I want to surprise him. His name is Andrew Yeoh Boon How and I heard he's quite active on Twitter. Can you help me find out when his birthday is?

Find the format of birth date they want. It is given in the flag - DD/MM/YYYY.

Go to twitter.com and search ‘Andrew Yeoh Boon How’. You do not need to login as it is a public account. It is the first result. Screenshots are below:

Figure 1: Screenshot of Andrew’s twitter profile.
Figure 1: Screenshot of Andrew’s twitter profile.

Scroll down to read his tweets. He only has 2 tweets. They do not give us any useful information. Screenshot is below:

Figure 2: Screenshot of Andrew's tweets

But hold up, let us revisit his profile page. Screenshot is below:

Figure 1: Screenshot of Andrew’s twitter profile.

He has stated his location (Singapore) and birthday (18 September). That’s great! But how about the year he was born in? Let us look closer at his username. Screenshot is below:

Figure 3: Andrew's Username

Bingo! The first part of the username is a shortened form of his full name, and he has very kindly added his year of birth as a suffix to his username. Now we know he was born in 1997.

Going back to the CTF website, key in the flag according to the given format - WH2021{18091997}. Done! Flag captured :)

Beanary over and out!