We explored possible strategies attackers can employ when abusing PowerShell Core. These proofs of concept (PoCs) would help in better understanding — and in turn, detecting and preventing — the common routines and behaviors of possible and future threats that attackers might use. The PoCs we developed using PowerShell Core were conducted on Windows, Linux, and mac OSs. Most of the techniques we applied can be seen from previous threats involving PowerShell-based functionalities, such as the fileless KOVTER and POWMET. The scenarios in our PoCs are also based on the PowerShell function they use.Read More
Trend Micro recently saw increased abuse of the internet query file IQY, similar to the activity detected in June from a Necurs-distributed spam wave that delivered the FlawedAmmyy RAT. It appears cybercriminals are taking advantage of the simple structure of IQY files because they can be used to evade structure-based detection methods.
Our latest observation found the Cutwail botnet distributing spam mails abusing IQY files. The spam campaign specifically targets users in Japan, delivering either the BEBLOH (detected by Trend Micro as TSPY_BEBLOH.YMNPV) or URSNIF (TSPY_URSNIF.TIBAIDO) malware. The spam mails attempt to trick users into clicking the attachment using conventional social engineering baits such as “payment,” “photos sent,” “photos attached,” and “please confirm,” among others. The campaign’s activity was detected on August 6, 2018, and has managed to distribute approximately 500,000 spam mails. The spam distribution has since died down on August 9.Read More
we found a new sample that may be related to the MuddyWater campaign. Like the previous campaigns, these samples again involve a Microsoft Word document embedded with a malicious macro that is capable of executing PowerShell scripts leading to a backdoor payload. One notable difference in the analyzed samples is that they do not directly download the Visual Basic Script and PowerShell component files, and instead encode all the scripts on the document itself.Read More
A malicious email campaign against Russian-speaking enterprises is employing a combination of exploits and Windows components to deliver a new backdoor that allows attackers to take over the affected system. The attack abuses various legitimate Windows components to run unauthorized scripts; this is meant to make detection and blocking more challenging, particularly by whitelisting-based solutions.
We’ve observed at least five runs from June 23 to July 27, 2017, each of which sent several malicious emails per target. Affected industries were financial institutions, including banks, and mining firms. Of note is how the attackers diversified their tactic—sending different emails for each run, per target.Read More
PowerShell is a versatile command-line and shell scripting language from Microsoft that can integrate and interact with a wide array of technologies. It runs discreetly in the background, and can be used to obtain system information without an executable file. All told, it makes an attractive tool for threat actors. There were a few notable instances…Read More