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ATM security analysis 3.0: PHDays 12 in review

Reading time 8 min
Views 420

 Python, Java, C++, Delphi, PHP—these programming languages were used create a virtual crypto ATM machine to be tested by the participants of the $NATCH contest at Positive Hack Days 12. The entire code was written by ChatGPT and proved to be exceptionally good. This time, we had reviewed the contest concept and decided to use a report system. In addition to standard tasks (kiosk bypass, privilege escalation, and AppLocker bypass), this year's participants faced new unusual tasks. Read on below to find out which ones.

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Rating 0
Comments 1

The Collatz conjecture is the greatest math trick of all time

Reading time 4 min
Views 2.4K

On the Internet and in non-fiction literature you can often find various mathematical tricks. The Collatz conjecture leaves all such tricks behind. At first glance, it may seem like some kind of a trick with a catch. However, there is no catch. You think of a number and repeat one of two arithmetic operations for it several times. Surprisingly, the result of these actions will always be the same. Or, may be not always?

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Total votes 7: ↑7 and ↓0 +7
Comments 2

Payment Village at PHDays 11: pentesting our online bank

Reading time 13 min
Views 751

Hello everyone! We've already talked in our blog about how the Positive Hack Days 11 forum had a special Payment Village zone, where anyone could look for vulnerabilities in an online bank, ATMs, and POS terminals. Our competition to find vulnerabilities in an online bank is not new, but in recent years it has been somewhat supplanted by ethical hacking activities for other financial systems. In 2022, we decided to correct this injustice and created a new banking platform, making use of all our years of experience. We asked the participants to find typical banking vulnerabilities and report them to us. In the competition, the participants could play for either the "white hats" (participate in the bug bounty program of an online bank) or for the "black hats" (try to steal as much money from the bank as possible).

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Rating 0
Comments 0

Payment Village at PHDays 11: ATM hacking

Reading time 7 min
Views 1.2K

The Positive Hack Days 11 forum, which took place May 18–19, 2022, was truly epic. The bitterly fought ATM hacking contest featured no fewer than 49 participants. How cool is that? The winner of this year's prize fund of 50,000 rubles, with the handle Igor, was the first to hack the virtual machines. And he wasn't even at the event! :)

Besides Igor, eight other participants picked up prizes this year for their VM-hacking skills. They were: drd0cvientvrazovdurcmzxcvcxzas7asg_krdhundred303, and drink_more_water_dude. A big thank-you to everyone who took part, and for those who weren't at PHDays, here are the links to the virtual machines.

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Total votes 5: ↑3 and ↓2 +1
Comments 1

Russian AI Cup 2020 — a new strategy game for developers

Reading time 5 min
Views 2.3K

This year, many processes transformed, with traditions and habits being modified. The rhythm of life has changed, and there's more uncertainty and strain. But IT person's soul wants diversity, and many developers have asked us if annual Russian AI Cup will be held this year. Is there going to be an announcement? What is the main theme of the upcoming championship? Should I take a vacation?

Though some changes are expected, it will be held in keeping with the best traditions. In the run-up, we will announce one of today's largest online AI programming championships — Russian AI Cup. We invite you to make history!
Total votes 15: ↑15 and ↓0 +15
Comments 0

СodeSide. The new game for Russian AI Cup

Reading time 3 min
Views 2.3K

The AI Cup community and Mail.ru Group in collaboration with Codeforces.com invite you to the real battle! Get ready for the sleepless nights and calloused hands — take part in Russian AI Cup, which is one of the most challenging and vivid artificial intelligence programming competitions in the world. Believe us, managers of this madness did their best to create the game you'd want to play.

To become part of the competition, you need Internet access, computer, creativity, and enthusiasm for being a part of this extraordinary Cup. By the way, you might need some coffee. Welcome!

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Total votes 33: ↑33 and ↓0 +33
Comments 1

How to quickly prepare for a job interview with questions on algorithms and technologies

Reading time 6 min
Views 2.9K
Greetings to all readers of Habr! My name is Yuriy, I have been teaching high technologies, Oracle, Microsoft and others for more than 20 years, as well as creating, developing and supporting loaded information systems for various business customers. Today I would like to tell you about the current direction: interviews on data processing technologies. The Russian variant of this post you can find here.

It doesn't really make sense for an employer to ask the applicant about traditional programming technologies. That is why I'm going to tell you how to prepare for an interview in only one narrow area related to information processing languages, namely, the processing of long integers(long arithmetic) and the identification of information properties of real world objects, which are described in long integers.
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Total votes 8: ↑6 and ↓2 +4
Comments 0

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