The tools of the gods

Today at SAW we are not going to talk about security but about religion. About the true religion, the good one: about Unix. And about its gods: Kernighan, Ritchie, Thompson … we could cite a few. And about the tools that, in the seventies, these gods sent to us poor mortals, like the manna fallen from heaven for the chosen people.

The thing is that these gods created a real operating system, with some technically wonderful tools and a very simple philosophy: simple capabilities that combined make complex tasks. Perfection. Life is Unix running a script. More than forty years have gone by and we, poor mortals who were the chosen people, what have we done all this time? Trying to dishonor that divine legacy with artificial and useless layers (“of abstraction”, they call them, to try to make sense of them) that introduce two unnecessary problems in any “modern” technological environment: complexity, and therefore probability of error, and slowness.

Exemplary is the “true” executable, in line with the story recently commented by Rob Pike on Twitter:

$ >mytrue;chmod +x mytrue
$ ./mytrue
$ echo $?

A program whose only purpose is to always return 0. An empty executable. EMPTY. There can be nothing simpler that works, and has been for forty years … well, that’s where we mortals come in. Year 2018:

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‘Reversing’ of malware network protocols with ‘angr’

One of the most difficult objectives to obtain in the analysis of a malicious binary is usually discovering all of the functionalities that it has. If in addition, these functions are only executed at the discretion of the attackers through its control center, things get complicated. For various reasons, many times we cannot carry out a full dynamic analysis, such as the fall of the malware infrastructure or the isolation of the sample to avoid contact with the C&C. In these cases the analysis of the interaction between the server of the attacker and the sample is usually slower, since you have to create a fictitious server or be continually patching/deceiving the sample, to take it through all the different paths that we want to investigate. Depending on the size and complexity of the analyzed code or the objective of the analysis, this task can vary its difficulty and extension over time.

I am going to propose a study example of the functionalities of a fictitious RAT that can be executed according to the orders received from your C&C panel. Our goal would be to create a server that simulates the attacker’s. For this we have to understand the communication protocol between the server and the sample installed on the victim’s device.

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Security of blockchain-based smart contracts II – Known Vulnerabilities and Pitfalls

In the previous part of this series on blockchain security we looked at the risks associated with deploying autonomously executing smart contracts on a public blockchain. We also introduced some high-profile examples of attacks on smart contracts that have caused the loss of large sums of money and changed the way we look at business interactions on the blockchain.

In this episode we will review some known issues and vulnerabilities.

Private Key Leakage

Using unsafe private keys is really a case of user error, rather than a vulnerability. However, we mention this nevertheless, as it happens surprisingly often, and certain players have specialized in stealing funds from unsafe addresses.

What usually happens is that development addresses (such as those used by testing tools, such as Ganache/TestPRC) are used in production. These are addresses generated from publicly known private keys. Some users have even unknowingly imported these keys into wallet software, by using the original seed words used in private key generation.

Attackers are monitoring these addresses and any amount transferred to such an address on the main Ethereum network tends to disappear immediately (within 2 blocks).
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Analysis of Linux.Okiru

In keeping with our campaign of detection and documentation of IoT botnets, a few days ago we found another threat not classified before. It was first uploaded to the VirusTotal platform on November 3 and is only detected as malicious by 4 antiviruses.

During the article, two variants of the malware will be analyzed, which differ fundamentally in their propagation. The first one was detected in our honeypot systems (specifically for the SPARC architecture). The second one is a variant of the first, which was found under the Intel x86_64 architecture, and which the Netlab360 malware lab echoed a few days ago.

As no records of its identification were found, we decided to classify it as Linux.Okiru, due to the name of its binaries.
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Publication of the NIS Implementation Regulation (for digital service providers)

(This entry has been prepared in collaboration with Ana Marzo, from Equipo Marzo, which provided a good part of the information).

Just a couple of weeks ago Ana March, from Equipo Marzo, an attorney for whom I have great professional respect, contacted me to tell me about the publication, not expected (at least by me), of a new regulation of the Commission related to the NIS Directive, which I have called in a display of originality NIS implementation regulation.

In fact, on 30 January, the Implementing Regulation (EU) 2018/151 of the Commission from 30 January 2018 was published, laying down rules for the application of the Directive (EU) 2016/1148 of the European Parliament and of the Council with regard to the specification of the elements to be taken into account by digital service providers in order to manage the existing risks for the security of networks and information systems, as well as the parameters for determining whether an incident has a significant impact..

At least it caught me by surprise (and I am sure that some of our readers will see the same thing), since I expected a transposition of the directive, not a regulation emanating directly from the Commission (which does not mean, of course, that we will not enjoy our own NIS-compliant legislation, as the legislator must be kept busy…). Given that, although in different areas, we had both coincided at the same client that fitted into the concept of digital services provider and could therefore be affected, we asked ourselves about the applicability of the regulation to this specific client. For example, is an online newspaper affected? And an online sales website? An online bingo? And the purchase-sale between individuals? Deriving the answer to these questions is the subject of this entry.
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Security of blockchain-based smart contracts I

Recently, blockchain technology has been advocated as a game changer for many industries. Distributed ledger technology that has emerged out of Bitcoin has promising applications beyond digital currencies.

One of the most promising use cases of blockchain technology is the development of smart contracts.

Smart contracts are self-executing contracts, in which the terms are specified in code. Essentially, this means encoding legal contracts in computer code, which executes them automatically.

Whilst the concept has been around for a while, at least since Nick Szabo’s wrote up the concept in 1996, it was not until the advent of the Turing-complete Ethereum blockchain that smart contract use became common.

Contracts on the Ethereum blockchain exist at contract addresses and can be invoked by transaction calls.

Executing contracts written in code and stored on an immutable public blockchain creates certain risks and issues, which we will discuss in a general way in this post. In an upcoming second part, we will look at more specific examples of smart contract security vulnerabilities. [Read more…]

Linux.IotReaper Analysis

A couple of days ago we learned about the existence of a new threat IoT considerably more elaborated than any of the ones detected to date (, said botnet has been named by Netlab 360 as IotReaper. So, from the malware laboratory of S2 Grupo we have obtained and analyzed some of the related samples.


The infrastructure of the network is quite similar to that of the Mirai botnet, which is formed by four elements:

  • Report Server: Responsible for collecting the information sent by the bots.
  • Server Downloader: Responsible for providing malware samples via HTTP. The presence of an element allows the continuous incorporation of updates without the need to leave obsolete versions of the malware.
  • Server C2: Responsible for sending denial of service orders.
  • Bot: IoT device infected by the IotReaper botnet.

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The Russian ICC (XVIII). Conclusions

For a few months we have published a series of posts about Russian cyber intelligence in SecurityArtWork, which we hope you have liked and they have helped you to better understand Russian capabilities, groups, structures, APT… without a doubt, Russia has been and continues to be one of the main players in the field of security, intelligence and defense (and of course in cybersecurity, cyber intelligence and cyber defense … or cyber things in general) and, as such, we must know it well if we work on these issues.

As we have seen in this series, Russia is a world power in many fields (as was the USSR in its day) and still retains Soviet reminiscences; the “Cold War Mode”, which we have referred to in different posts, perfectly defines its current cyber strategy and the management of information that the country has historically done, which are applied in this broad concept of information warfare which we have also referred to on many occasions, significantly different from the West, and which includes propaganda or deception, to give just a few examples. If Russia is your mother and your mother is in danger you will do whatever is necessary to save her. Period. No further discussion.
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The Russian ICC (XVII): objectives. Spain

The First General Directorate of the KGB was responsible for all operations of the service outside the USSR; this Directorate included departments focused on different geographical areas of the world, which were the operational nucleus of the General Directorate and were responsible, among other things, for the duties of almost all KGB-linked companies operating outside Soviet territory. And within these geographical departments, the Fifth was concerned with France, Italy, the Netherlands, Ireland … and Spain. Certainly we did not reach the level of the United States and Canada (First Department, exclusively occupied by these two countries) but we were not very far, perhaps on a second level. For different reasons that have obviously changed over the years, since the Civil War until now Spain has been a historical objective (not the most important, but relevant) for Soviet intelligence and now it is still so for Russian intelligence: from the NKVD during its lifetime to the current services, obviously passing through the KGB from the middle to the end of the last century. Exactly the same as the USSR, or Russia today, it also is and has been an important objective for the West: for example, we have only to read something about the operation Mari, in the 60s ([2]).... Leer Más

The Russian ICC (XVI): objectives. Countries

Any country in the world is a potential target of Russian-or non-Russian-espionage. As an example, infiltration in America has historically been high, not only in the United States, a country of highest priority for Russian intelligence, but also throughout Latin America.

However, the maintenance of a large ecosystem of intelligence is not cheap – although it is certain that, thanks to the particularities and relations of the Russian services, it is not as expensive as it would be in other circumstances. So as in any country, Russians should prioritize their usual activities and interests, leaving for temporary occasions those temporary objectives: for example, the Middle East (Syria, Iran …) can be considered in the list of these temporary objectives, for reasons of security —counterterrorism— as well as economic —customers or suppliers of basic goods for Russia.

In addition to these, countries such as Australia or New Zealand, technologically developed and close to the West —not from the physical point of view, of course —are also targets of Russia for different reasons, such as industrial espionage. We have highlighted in gray the target countries of Russian espionage:

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