Information Security *

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: drd0c, vient, vrazov, durcm, zxcvcxzas7, asg_krd, hundred303, 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.

The National Internet Segment Reliability Research explains how the outage of a single Autonomous System might affect the connectivity of the impacted region with the rest of the world. Generally, the most critical AS in the region is the dominant ISP on the market, but not always.

As the number of alternate routes between ASes increases (the "Internet" stands for "interconnected networks" - and each network is an AS), so does the fault-tolerance and stability of the Internet across the globe. Although some paths are more important than others from the beginning, establishing as many alternate routes as possible is the only viable way to ensure an adequately robust network.

The global connectivity of any given AS, whether an international giant or a regional player, depends on the quantity and quality of its path to Tier-1 ISPs.

Usually, Tier-1 implies an international company offering global IP transit service over connections with other Tier-1 providers. Nevertheless, there is no guarantee that such connectivity will always be maintained. For many ISPs at all "tiers", losing connection to even one Tier-1 peer would likely render them unreachable from some parts of the world.

Imagine someone withdrew money from a company's account at night. The next morning panic breaks out, leading to yet more problems. The IT department can reinstall a compromised system from scratch or restore it from backup. Reinstalling from scratch will wipe out all traces left by the attackers, and external investigators will have to search for clues in other systems. Restoring from backup carries the risk of accidentally reinstating a compromised image. In this paper, we will describe common mistakes that experts make when responding to security incidents.

The second quarter of the year has ended and, as usual, we take a look back at the mitigated DDoS attacks activity and BGP incidents that occurred between April and June 2022.

The IDS Bypass contest was held at the Positive Hack Days conference for the third time (for retrospective, here's . This year we created six game hosts, each with a flag. To get the flag, participants had either to exploit a vulnerability on the server or to fulfill another condition, for example, to enumerate lists of domain users.

The tasks and vulnerabilities themselves were quite straightforward. The difficulty laid in bypassing the IDS: the system inspected network traffic from participants using special rules that look for attacks. If such a rule was triggered, the participant's network request was blocked, and the bot sent them the text of the triggered rule in Telegram.

And yes, this year we tried to move away from the usual CTFd and IDS logs towards a more convenient Telegram bot. All that was needed to take part was to message the bot and pick a username. The bot then sent an OVPN file to connect to the game network, after which all interaction (viewing tasks and the game dashboard, delivering flags) took place solely through the bot. This approach paid off 100%!

Comprehensive guide for iOS app security testing and reverse engineering.

The first text-based CAPTCHA ( we’ll call it just CAPTCHA for the sake of brevity ) was used in 1997 by AltaVista search engine. It prevented bots from adding Uniform Resource Locator (URLs) to their web search engine.

Back then it was a decent defense measure. However the progress can't be stopped, and this defense was bypassed using OCR available at those times (for example FineReader).

CAPTCHA became more complex, noise was added to it, along with distortions, so the popular OCRs couldn’t recognize this text. And then OCRs custom made for this task appeared. It costed extra money and knowledge for the attacking side. The CAPTCHA developers were required to understand the challenges the attackers met, what distortions to add, in order to make the automation of the CAPTCHA recognition more complex.

The misunderstanding of the principles the OCRs were based on, some CAPTCHAs were given such distortions, that they were more of a hassle for regular users than for a machine.

OCRs for different types of CAPTCHAs were made using heuristics, and the most complicated part of it was the CAPTCHA segmentation for the stand along symbols, that subsequently could be easily recognized by the CNN (for example LeNet-5), also SVM showed a good result even on the raw pixels.

In this article I’ll try to grasp the whole history of CAPTCHA recognition, from heuristics to the contemporary automated recognition systems. We’ll figure out, if a CAPTCHA is still alive.

I’ll review the yandex.com CAPTCHA. The Russian version of the same CAPTCHA is more complex.

Positive Hack Days 11 will begin in a matter of weeks. This international forum on practical security will be held on May 18–19 in Moscow.

As per tradition, PHDays will have three big tracks dedicated to countering attacks (defensive), protection through attack (offensive), and the impact of cybersecurity on business. It is our pleasure to present the first talks.

The first quarter of the year 2022 has passed; now, it is time to look at the events of Q1 in terms of mitigated DDoS activity and recorded BGP incidents.

You decided to make an app that works with SVG. Encouraged by the enthusiasm, you collected libraries and successfully made the application. But suddenly you find that the app is sending strange network requests. And data is leaking from the host-machine. How so?

How can simple XML files processing turn into a security weakness? How can a blog deployed on your machine cause a data leak? Today we'll find answers to these questions, learn what XXE is and how it looks like.

When you have an IT, which supports all aspects of your organization automated performance and you have a firm confidence that IT executes well, there is always a chance that something could go wrong in technology or in related IT processes. Depending on complexity of IT environment varieties of risks scenarios could arise. This article as a summary of different faithworthy sources aims to help you in getting high level understanding on what could go wrong and how you can predict it in a more conscious way.

My name is Maxim Tornov and I have been working in various IT areas for a long period of time. Since then, for over 14 years I am working in the area of IT/IS risk management with focus on in IT/IS audits, internal control implementation and assessment.

I am sure that at the present the topic of Information Technologies risk management became more vital. Organization’s efficiency in IT risk management directly affects the achievement of various organization’s goals, goals which have dependency on IT, those goals may include reliability and efficiency of business processes, the organization's compliance with regulatory requirements, the integrity of financial reporting, and many others.

I sincerely hope that this material will be useful to you and may give you some new ideas that you can contribute to the benefit of your personal development and the development of your organization's risk management culture.

2021 was an action-packed year for Qrator Labs.

It started with the official celebration of our tenth year anniversary, continued with massive routing incidents, and ended with the infamous Meris botnet we reported back in September.

Now it is time to look at the events of the last quarter of 2021. There are interesting details in the BGP section, like the new records in route leaks and hijacking ASes, but first things first, as we start with the DDoS attacks statistics.

Link to GitHub. More details about the operation of the algorithm and the module can be found here.

The ACME protocol client is used to automatically obtain a security certificate for your site. Basically everyone uses Let's Encrypt to get a free certificate and auto-renewal. But there are other services, such as Zero SSL. It also supports the ACME protocol.

I relied on two articles from Habr (this and this), as well as RFC8555. But the information in them was not enough to implement their own version of the modulation. At least several times higher than several implementations of the module [at another level]. The tests were conducted on a live service, so there are no autotests yet. You can write and init pull request.

The module is written under Linux. Only the second version of the protocol is considered.

• A short excursion into WeChat;
• About the platform, the version of the application, the utilities used and the decryption of the executable file;
• • About two protocols (old one and new one);
• About serialization of objects;
• Used cryptography and key exchange;
• About headers and hash-functions;
• About the exposures found.

Comprehensive manual for iOS app security testing and reverse engineering.

Application Programming Interfaces or API’s are responsible for majority of system integration and functional components of modern computing landscape in both consumer and enterprise environments.

Properly constructed secure API’s provide significant benefits during initial build, integration with other systems and during entire application lifecycle while protecting sensitive information stored in business systems.

Based on author's experience designing and implementing API’s for variety of clients in financial, insurance, telecom and public sectors, security is often overlooked in favor of simplistic, vendor/product specific solutions.

This article addresses best practices for API security design in product neutral manner to help architects to plan and build easy to work with and secure API's.

Recommended approach is to separate API security from its business functionality and allow back-end developers to concentrate only on business functions. Once business logic for an API is ready, it can be published using common security components described in this article.

This article does not provide any product specific recommendations, but any modern API security/governance platform will be able to satisfy majority of suggested requirements using out-of-the-box functionality.