Case study: “Imminent RATs” (III)

Articles from the series “Case study: “Imminent RATs”: [1] [2] [3]

Note: This is a fictional story; the characters and situations are not real. The only real thing is the technological part, which is based on a mixture of work done, experiences of other colleagues and research carried out.
These articles are part of a basic incident response workshop. Therefore, there are things that could be done more efficiently and elegantly… but the idea was to do them in a simple way so that they were easy to understand. And like any good practical workshop, you can follow it step by step: you can download a Remnux virtual machine with everything you need for the workshop here (for VMWare) or here (.ova format))

Additional analysis

The incident was practically solved in the previous article, but we still have some doubts in the pipeline:

  • What actions did the malware perform on the system?
  • What type of malware is it?

To get out of doubts we execute the document in a specially tuned virtual machine with anti-VM measures, which also has Noriben and Sysmon installed. In addition, we capture the outgoing traffic with WireShark to have as complete a view as possible of what the malware does.
[Read more…]

Case study: “Imminent RATs” (II)

Analysis (follow-up)

In the previous article, we had determined there was “something weird” in the computer, and we had downloaded both, a possibly malicious .doc and a user executable and mailbox. It’s time to get down to work to see what they may contain…

[Note: As a good security practice, malicious files should NEVER be shared without minimal protection. Therefore, you can download both files from here, but they are zipped with the password “infected”. Please, handle them with extreme care, you’ve been warned.]

To start with, we can open the user’s .pst to verify that the infection path is correct, something we can easily do from Windows with the Kernel Outlook PST Viewer:
[Read more…]

Case study: “Imminent RATs” (I)

Note: This is a fictional story; the characters and situations are not real. The only real thing is the technological part, which is based on a mixture of work done, experiences of other colleagues and research carried out.
These articles are part of a basic incident response workshop. Therefore, there are things that could be done more efficiently and elegantly… but the idea was to do them in a simple way so that they were easy to understand. And like any good practical workshop, you can follow it step by step: you can download a Remnux virtual machine with everything you need for the workshop here (for VMWare) or here (.ova format)).

Incident Response in less than 15 lines

Ultra-fast summary of incident response:

  • Preparation: We prepare ourselves for a possible attack by deploying detection and response measures in the Organization.
  • Detection and analysis: We detect possible attacks and analyze them to determine whether or not they are false positives, and in the event of an attack we analyze its severity.
  • Containment, eradication and recovery: We contain the spread of the attackers through the system, expel them and return the system to normal operation.
  • Post-incident lessons: We analyze the incident in search of measures to improve both the security of the system and the response itself for future incidents.

[Read more…]

Security in Windows Server 2019

At the end of last December, Microsoft published a document titled What’s new in Windows Server 2019, covering the new features and renewed functionalities provided by the new version of Windows Server. This post will focus on those features related to security improvements provided by Windows Defender ATP that had already been seen in Windows 10 through Windows Defender Exploit Guard, EMET (Enhanced Mitigation Experience Toolkit, which ceased to have support last July 31, 2018), as well as WDAC (Windows Defender Application Control).... Leer Más

EternalSilence: Why your router may be at risk from this NSA tool

Today’s article is courtesy of John Mason, co-founder of  TheBestVPN.com and writer at TripwireStaySafeOnline, DigitalGuardian y Educause. You can find him on twitter as @JohnCyberMason.

Do you trust your router to keep you safe from hackers and spies? You may want to take another look just to make sure.

Akamai recently discovered a malware campaign that has already compromised over 45,113 home and office routers. This was done using a tool based on the United States of America’s NSA hacking tools which were leaked online in 2017. To explain how hackers use this tool to turn your router into a proxy server, we first have to understand how UPnP works.

UPnP is a protocol that eases device and service discovery as well as the configuration of consumer devices and networks. Its primary purpose was to allow devices on a LAN to automatically expose services and functionality other devices on the local network.

[Read more…]

Analysis of Linux.Haikai: inside the source code

A few days ago we got the source code of the Haikai malware, which corresponds to one of the many implementations carried out by the continuous recycling of source code belonging to different IoT botnets. Although we have not identified any new developments compared to previous IoT malware versions, it has allowed us to obtain a lot of information on techniques, improvements and authors.

It should also be noted that, according to different records obtained, this botnet has been in operation for most of the last month of June.

In the following lines the code will be analyzed, as well as the possible attributions and the implementations not referenced in the execution thread, which allow us to guess that the code is mutating in different lines in parallel for the same function.

So let’s start by analyzing the structure of the files. [Read more…]

‘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.

[Read more…]

Some vulnerability in ASUS routers

A few months ago, I changed my old TP-LINK router to an ASUS. Since it is the de facto manufacturer recommended by my ISP, in order to avoid any complications that could lead to delays in getting my Internet up and running I decided to go with it.

Then comes a lonely afternoon of boredom, or perhaps out of habit (I wanted to start writing a report:D), so I start by trying a little apostrophe here, a marquee as the Wi-Fi name, , command execution in one of the network diagnostic pages and a long list of etc. In the end, one thing leads to another (you know how that goes…), you get involved and when you’re conscious you have Burp or ZAP open, you’ve gone over halfway through OWASP and you’ve been looking for hours for something to play with, something interesting to see how safe your brand-new router is. [Read more…]

Templates with bad intentions

A few days ago while analyzing several emails I came across one that contained a suspicious attachment. It was a .docx document that at first glance had nothing inside but it occupied 10 kb.

The mail had passed all the barriers, both SPF, as the two antiviruses that gateways have, and also the anti-spam filter.

The .docx file can be treated as a tablet. Once extracted its content, I began to analyze all the files in the directory in search of domains or IP addresses that could be seen clearly:

And I managed to find something interesting inside the path word/_rels/document.xml.rels where the following appears:
[Read more…]

Phishing: improving our campaigns

One of the most important things when carrying out a phishing campaign [Obviously, always from legal terms Ed.] is to ensure that our mail gets to evade the anti-spam filters and thus be able to reach the victim’s inbox.

In this post we are not going to explain how Gophish, que ya hemos mencionado en algún post, we will simply explain a series of steps to follow to make our emails more reliable. It is worth adding that following these steps does not ensure 100% success, each mail manager has its own filtering rules.

We start from the basis that Gophish is already installed, so the next step would be to obtain a domain and make a series of changes in DNS administration.
[Read more…]