The DoNot APT (aka APT-C-35) has been active since 2016. They have attacked many individuals and organisations in South Asia. DoNot APT is reported to be the main developers and users of frameworks for developing Windows and Android malware.
This group mainly targets organisations in India, Pakistan, Sri Lanka, Bangladesh and other South Asian countries. They focus on government and military organisations, foreign ministries, and embassies.
For the initial access, DoNot APT uses phishing emails containing malicious attachments. To get to the next stage, they execute a macro embedded in an MS Office document which drops a PE file and executes them. We have witnessed this PE file being a DLL file in the past campaigns. There is a change in the initial access of this APT group. The RedDrip Team, tagged a ZIP (filename: “Day .zip”) file being part of the DoNot APT campaigns. The lure was themed to leverage geopolitical tensions between India and Pakistan as shown in Figure 1. The ZIP file is bundled with a WinRAR SFX executable, which contains a DLL file and PDF files under a folder named “Kashmir”.
The SFX executable executes that DLL as shown in Figure 2. The DLL file is responsible for connecting to the C2. The C2 Server was down at the time of writing this blog.
The domain registrar for the C2 domain (briefdeal.buzz) is NameSilo Inc, which seems to be a pattern since September 2022. The DLL contains 2 export functions. The first function creates mutex (“olgui1pigg”) as a marker for infection and then establishing connection to C2 and the next function is for self copying itself to the %TEMP% folder and creating a scheduled task for persistence by setting a new Scheduled Task that runs every four minutes. The action assigned to the task is to run the first export function. The C2 server was down during our analysis.
It tries to send the basic info of the Victim’ PC to the C2 like Username, Computer Name, Processor ID.
Here we mentioned the timeline of samples which are used by DoNot APT from Sep 2022 to Jan 2023.
|Time||Samples File Name|
|Jan 2023||Kashmir Solidarity Day Material .exeRequirement of pattenization data for seamanship items.xls|
|Nov 2022||Requirement list of spares.xls|
The C2 URL TLD has been .buzz since the September 2022 campaign. The DNS registrar for the C2 URL is NameSilo Inc. and the IPs resolved to the ASN number 399629. Based on the ASN number we were able to deduce the ISP as BL Networks, and from there we were able to track it to a Virtual Private Server (VPS) provider called BitLaunch, which accepts crypto payments. We found evidence of this particular VPS service being used for malicious campaigns in the past. We found this pattern to be consistent since September 2022.
We at K7 labs provide detection against such threats. Users are advised to use a reliable security product such as “K7 Total Security” and keep it up-to-date so as to safeguard their devices.
|4EAA63DD65FC699260306C743B46303B||Kashmir Solidarity Day Material .exe|
|06ADBB4BA31A52CC5C9258BF6D99812C||Requirement list of spares.xls|
|DC6DF9BDEE372A00E5402C19D2D77DE9||Requirement of pattenization data for seamanship items.xls|
|64266FC0F0B37A26E14133AD19B98B7C||Requirement list of spares.xls|