This blog discusses targeted attacks against the Middle East taking place between February and October 2017 by a group Unit 42 is naming “MuddyWater”. This blog links this recent activity with previous isolated public reporting on similar attacks we believe are related. We refer to these attacks as MuddyWater due to the confusion in attributing these attacks. Although the activity was previously linked by others to the FIN7 threat actor group, our research suggests the activity is in fact espionage related and unlikely to be FIN7 related.
The MuddyWater attacks are primarily against Middle Eastern nations. However, we have also observed attacks against surrounding nations and beyond, including targets in India and the USA. MuddyWater attacks are characterized by the use of a slowly evolving PowerShell-based first stage backdoor we call “POWERSTATS”. Despite broad scrutiny and reports on MuddyWater attacks, the activity continues with only incremental changes to the tools and techniques.
Introduction & Overview
The Palo Alto Networks Unit 42 research team recently came across a series of malicious files which were almost identical to those targeting the Saudi Arabian government previously discussed by MalwareBytes. Which in turn, closely resembles a previous article by Morphisec. These attacks have also been tracked by several other researchers on Twitter and elsewhere.
The activity has been consistent throughout 2017 and, based on our analysis, targets or is suspected to target, entities in the following countries:
- Saudi Arabia
- United Arab Emirates
The malicious documents were adjusted according to the target regions, often using the logos of branches of local government, prompting the users to bypass security controls and enable macros. An overview of the technical changes seen in the past year is given in the graphic below, note that raw IOCs present in this graphic can be found as text in the Appendix at the end of this article.
Figure 1. An overview of the delivery of POWERSTATS, C2 URLs used, and other changes in the malware
MuddyWater in the Middle East
The attackers behind MuddyWater have been active throughout 2017, with targets across the Middle East and surrounding areas, a summary of the decoy documents observed is given in Table 1.
Of course, being named in a decoy document doesn’t mean any of these organizations have been attacked themselves or are involved in the attacks: the MuddyWater actors are abusing the trust these organizations’ names and/or logos command for their malicious purposes.
||File Name or Decoy Document Theme
||Suspected Target Region
Pakistan Federal Investigation Agency
CV of Middle Eastern Civil Servant
||Iraq National Intelligence Service
Kaspersky Security solution 2017.doc
||Arab Emirate سری.docm
Iraq Commission of Integrity
||Requirements of the Sago.doc
||Iraq Kurdistan Regional Government
Iraq Kurdistan Regional Government
Table 1 – A summary of the lure documents observed in the MuddyWater attacks.
All of these documents we observed and outlined above are related via:
- Shared C2 infrastructure.
- Use of the non-public PowerShell backdoor previously described by Morphisec and MalwareBytes (which we refer to as POWERSTATS).
- Shared attributes of the malicious documents used in attacks.
- Shared attributes as to how the documents were delivered.
Based on these connections we can be confident that all the files and infrastructure we give in our appendices are related, since more than one of these can be used to link each of the samples discussed in each case.
I download my tools from GitHub, and so do my victims.
The tools used by the MuddyWater attackers have been well documented by the previously cited research and a common theme of previous reporting was the open source nature of much of the toolset used by MuddyWater: Meterpreter, Mimikatz, Lazagne, Invoke-Obfuscation etc.. In some of their recent attack documents, the attackers also used GitHub as a hosting site for their custom backdoor, POWERSTATS. Specifically, the following GitHub repositories appear to be controlled by the MuddyWater threat actor(s):
- [unknown SHA256]
- Downloads payload from: hxxps://raw.githubusercontent[.]com/F0R3X/BrowserFontArabic/master/ArabicBrowserFont.exe
- [unknown SHA256]
- Downloads payload from: hxxps://raw.githubusercontent[.]com/F0R3X/BrowserFontArabic/master/FontArabic.exe
- 9b5e36bb7518a9e333c31d09b589102f89e3425571dd434820ab3c437dc4e0d9 (and several others)
- Downloads payload from: hxxps://raw.githubusercontent[.]com/ReactDeveloper2017/react/master/src/test/test.js
Interestingly, both profiles were populated with forked repositories to give them an air of legitimacy as shown in figure 2. The POWERSTATS malware was compiled as an exe using PS2EXE. However, this was a minor anomaly, as it was only seen in this case: raw scripts being used in all other cases.
Figure 2 – The GitHub profile for F0R3X containing both legitimate forked code and the binaries created by the attacker. Note that the username could be a small joke on the attackers’ part regarding the attribution to FIN7.
Pwn one to pwn them all
In some of the instances we observed what appeared to be compromised accounts at third party organizations sending the malware. In one case, the attackers sent a malicious document which was nearly identical to a legitimate attachment which we observed later being sent to the same recipient. This indicates that the attackers stole and modified a legitimate document from the compromised user account, crafted a malicious decoy Word macro document using this stolen document and sent it to the target recipient who might be expecting the email from the original account user before the real sender had time to send it.
This targeting of third party organizations to attack further targets is a risky move on the attackers’ part, as it potentially reveals their activity within the compromised third party organizations to the new target (those receiving the malicious documents
Making sense of MuddyWater
When we looked at the cluster of activity which consisted of what appeared to be espionage-focused attacks in the Middle East, we were somewhat confused as the previous public reporting had attributed these attacks to FIN7. FIN7 is a threat actor group that is financially motivated with targets in the restaurant, services and financial sectors. Following the trail of existing public reporting, the tie to FIN7 is essentially made based on a download observed from a MuddyWater C2, of a non-public tool “DNSMessenger”.
For example, Morphisec wrote:
“Later in our investigation, the same command server also delivered a variant of the DNS messenger similar to that described by Talos. The domain names differed but the script adheres to the same logic (including the logic function).”
The DNSMessenger malware is an obfuscated and customized version of the popular DNS_TXT_PWNAGE.ps1 script available on GitHub and is also referred to by FireEye as POWERSOURCE. The use of the DNSMessenger tool appears primarily linked to FIN7, with no other samples being attributable to MuddyWater.
This led us to query the relationship between the newer attacks we were looking at and the alleged FIN7 link. As part of this research, we came up with the following hypotheses along with their likelihoods, and a rationale for each one.
1) The FIN7 threat actor is also involved in espionage in the Middle East – Unlikely
Whilst this may seem an attractive hypothesis to some, there are aspects on the technical side that simply don’t add up. Primarily, there are significant disparities between FIN7 and MuddyWater, specifically in terms of:
- Malware unique to FIN7, or commonly used by them has not yet been seen in any MuddyWater investigations (except for the single observation of the DNSMessenger sample)
- Other non-public malware and tools used by MuddyWater have not been observed in our FIN7 investigations.
- From an infrastructure point of view there is no overlap between the two sets of activity, the only overlap is the use of the unique tool “DNSMessenger”
When these points are considered together in conjunction with the significant difference in targeting they make a strong case for classifying this activity as distinct from FIN7 activity.
2) The DNSMessenger malware is a shared tool, used by FIN7, MuddyWater and perhaps other groups – Unlikely
We have attempted to find examples of code available in public data sources that would generate the variation of the DNSMessenger malware and had little luck in doing so. Even though the code for DNSMessenger is publicly available following research into attackers published by 3rd parties, attackers would have to write the corresponding server side to use it, and as such they may well choose to use the public DNS_TXT_Pwnage.ps1 script instead.
Despite this, based on the chain of analysis above we cannot discount the notion that DNSMessenger is shared by multiple attackers, including FIN7 and MuddyWater.
3) There was a mistake in the original Morphisec analysis which linked these attacks to FIN7 – Possible
Little detail is given on the nature of how the connection between DNSMessenger and MuddyWater was discovered it isn’t possible for us to verify this link.
4) The attackers realized they were under investigation and planted a false flag – Possible
The attackers realized they were under investigation and planted a false flag on their C2 server, uploading a copy of the FIN7 DNSMessenger code which had been previously mentioned (and was since publicly available) by FireEye and delivering it to researchers to trick them into mis-attributing the campaign.
Indeed, the sample shared by Morphisec on PasteBin is identical to the one dropped by the sample discussed in the FireEye FIN7 SEC campaign blog except for the final line.
Whilst we could conclude with confidence that the attacks discussed in this article are not FIN7 related, we were not able to answer many of our questions about the MuddyWater attacks. We are currently unable to make a firm conclusion about the origin of the attackers, or the specific types of information they seek out once on a network. In any case we will continue to track their activities to provide protections for our customers.
We hope the analysis presented shows the importance of drawing your own conclusions based on the data available to you, not just taking the conclusions given in the public domain at face value. This is especially true when actors who rely on slightly modified (and publicly available) open source tools are in play. Copycat threat actors can easily mimic attackers who use open source tools which can confuse attribution efforts meaning more than one aspect of the attacks observed must be considered when clustering.
On top of this, whilst the vast majority of threat analysis in the public domain is repeatable and correct, in some cases it can be difficult to verify the analysis available. When it is hard to reproduce the analysis the confidence in any conclusions drawn must be lower than it would otherwise be, since you cannot know for sure that what is stated is true.
Palo Alto Networks customers are protected from this threat in the following ways:
- WildFire and Traps detect all the malware supported in this report as malicious.
- Traps customers can deploy Heuristic methods to detect attacks that use these techniques.
- C2 domains used by the attackers are blocked via Threat Prevention.
AutoFocus customers can monitor ongoing activity from the threats discussed in this report by looking at the following tags:
Appendix A – C2 Addresses
Compromised Legitimate Sites
Appendix B – Related files
||Loader script from 144.76.109[.]88
||PS2EXE PowerStats (GitHub)
||PS2EXE PowerStats (GitHub)
||Decoded PowerStats payload
||Lazagne Runner Script
Appendix C – Proxy URLs found from POWERSTATS samples from October 2017 onwards
The post Muddying the Water: Targeted Attacks in the Middle East appeared first on Palo Alto Networks Blog.