UIUCTF 2020

Miscellaneous

jc01010

July 20th, 2020

Discord
Bots

If you solve this challenge, straightup you have Omega Stonks. (Buy this flag from IsabelleBot)

First, I have to thank our amazing group of friends, AC, Bacon, as well as our imaginary friends JC01010, JC01010, JC01010, and JC01010 for helping out with this challenge - without them, we could not have solved this challenge.

Three members of our team, Bacon, AC and I decided to play around with the bot. Unsure of whether or not the bot had a challenge meant for it, we !work-ed a bit but didn't get far. However, as soon as the "Omega Stonks" challenge was uploaded, we went for the flag.

Our strategy was simple. !work gave you between 100 and 500 coins, with the expected value of 300 coins every 10 seconds. However, with 3 members, this could be tripled to 900 coins every 10 seconds.

This leads to a 5400 coins/min, or 324000 coins/hour. However, the bot slowed down tremendously due to the immense load put onto the bot by people using macros or bots. The flag cost 500,000 coins, so at a completely optimal pace, it would take approximately 1.543 hours, or 1 hour, 32 minutes and 34.8 seconds to get the flag.

However, discord's slow mode is broken! Since the slow mode counter starts from 10, and ends at 0, it actually takes 11 seconds for the slow mode to allow you to send another message.

Time to redo the math!

900 coins/11 seconds

4909.1 coins/minute

294546/hour

It would now take 1.69752772 hours, or 1 hour, 41 minutes and 51.1 seconds to get the flag.

That, combined with human error and it being midnight in New Jersey was almost a deal breaker. That is, until I realized I could use alt accounts.

My friends JC01010, JC01010, JC01010, and JC01010 generously allowed me to use their discord accounts to !work overtime. By using chrome, chrome's incognito tab, edge (disgusting), and edge InPrivate (incognito) mode, I could bot with 3 different accounts. On top of that, by using AC's old computer, I could use a 5th (and even 6th, 7th, 8th) accounts if I wanted. However, gmail was limiting my account creation usage so I decided against it.

We started using these accounts when were were at approximately 200,000 coins. This left us with 300,000 coins to go, and 7 accounts generating coins each at 300 coins/11 seconds.

Time for some more math!

7*300 coins/11 seconds = 2100 coins/11 seconds

11454.55 coins/minute

687273 coins/hour

Reaching 300,000 coins would take 0.44 hours, or 26 minutes, 11.43 seconds of perfect spamming between multiple different tabs, and 7 accounts between 4 people.

We captured some great moments: one can be seen here and here.

As a side note, one of my friends JC01010 got banned(?). Rest in peace, JC01010#7737; you will be missed.

After 4 hours of !working overtime and transferring credits to me, we finally reached 500,000 credits. Typing `!buy flag`

got us a flag and a dm from the Isabelle bot:

**Flag: uiuctf{so_much_money_so_much_time_enjoy_50_points_XD}**