lazarusholic

Everyday is lazarus.dayβ

PebbleDash - Lazarus / HiddenCobra RAT

2020-06-01, MalwareNailed
https://malwarenailed.blogspot.com/2020/06/peebledash-lazarus-hiddencobra-rat.html
#PebbleDash

Contents

PebbleDash - Lazarus / HiddenCobra RAT
Hi folks. I was analyzing the PebbleDash malware used by Lazarus APT group. While analyzing the original sample (Md5: d2de01858417fa3b580b3a95857847d5), I was able to find out the C2 server and the port, where it intends to communicate to. I also found an interesting technique it uses to identify the OS version of the victim machine.
During static analysis, I observed interesting strings were starting with "Zip-bug", as can be seen below. Using yara rules I was able to discover some other samples uploaded to HA (Hybrid Analysis) with the same strings embedded. These samples seemed to be not related to d2de01858417fa3b580b3a95857847d5. However, they communicated to South Korea and China.
While performing dynamic anlaysis, I observed that the sample uses the API call IsProcessorFeaturePresent to determine the version of the victim OS. The PF_FLOATING_POINT_PRECISION_ERRATA feature is explicitly set to FALSE in x86 version 6.1 and higher.
The sample loads …

IoC

112.217.108.138
d2de01858417fa3b580b3a95857847d5