CyberThreatIntel/Indian/APT/SideWinder/11-10-2019/Analysis.md
2019-10-14 23:07:30 +02:00

6.7 KiB

The SideWinder campaign continue

Table of Contents

Malware analysis

The initial vector is a malicious RTF file with an RTF exploit (CVE-2017-11882) for executing the package OLE from the doc.

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The first part of the JS payload is a function for decode the payload and resize the windows for hidden of the victim and is decoding the PE files in base 64.

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On the second part, this extracts the files on "C:\ProgramData\AuthyFiles" and use a function for detecting the version of NET for use the correct version of csc to use. Once this done, this uses the even tactical that the last time in using deserialized the serialized objects and push it by a "DynamicInvoke" in the current delegate.

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In the final part, this executes it in the memory the legit file (writer.exe -> Windows Write of Microsoft), the loader and the payload of the hijack.

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The loader copy a part of the payload and push in create a new process from the "write" process by process hijacking.

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This push an Run key or the persistence, show an error message for decoys the victims. This steals the configuration (Admin rights, IP config, system config, time zone, process, updates...), the list of documents on the disk and sent it to the C2 and wait for the commands.

Cyber Threat Intel

Files push in Appdata

The backdoor stock in the disk multiples files with differents results of the operations perform on the computer:
  • A file with a sif extension :
This content the system and user account informations steal by the backdoor and which send to the C2 when the connection is etablish (JSON file).

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  • Another file with the fls extension :
A second JSON file which content the list of the path of the document to steal and push on the C2 (target the xls, xlsx, doc, docx, pdf documents).

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A file with the extension flc is used by the process as debug for the edition of the fls file.

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Same IP as C2

Like the last analysis (in August 2019), the group use the same domain and IP as C2, we can observed that is probably active since may 2019.
IP Route ASN Organization Country City Coordinates
178.62.190.33 178.62.128.0/18 AS14061 DigitalOcean, LLC Netherlands Amsterdam 52.3740,4.8897

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Still continue to target China

Since the accord between China and Pakistan about the Kashmir crisis, the Indian APT SideWinder hasn't stopped attacking China, the last time this target the China event on the Chian's 2019 Defense White Paper and this time used to fake technical documentation.

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Cyber kill chain

The process graphs resume all the cyber kill chains used by the attacker.

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References MITRE ATT&CK Matrix

List of all the references with MITRE ATT&CK Matrix
Enterprise tactics Technics used Ref URL
Execution Execution through Module Load
Exploitation for Client Execution
https://attack.mitre.org/techniques/T1129/
https://attack.mitre.org/techniques/T1203/
Persistence Registry Run Keys / Startup Folder https://attack.mitre.org/techniques/T1060/
Credential Access Credentials in Files https://attack.mitre.org/techniques/T1081/
Discovery Query Registry https://attack.mitre.org/techniques/T1012/

Indicators Of Compromise (IOC)

List of all the Indicators Of Compromise (IOC)
Indicator Description
zhengce.doc b1417d7ee62878ef75381e4a3a4f388ac08ac4d4bbd9999b126345691e82b0c2
C:\ProgramData\AuthyFiles\PROPSYS.dll 4e12d1bf1a631b8045e267671c0340b8da61777480692c4ce396f932f6bd4023
C:\ProgramData\AuthyFiles\write.exe 45BD87A5803916409A0D824BEEFAFB1FAF49D52E0BA9C0E8014E82EAA17E7659
1.a c5feee527bb90926949c572bfe3fceb862727a9f5cee1fc580a11558253d624e
Authy 99542270c355bdaef251fefeaf88c5ff747e3837501735887e7b2b7b54e2e2f2
178.62.190.33 IP C2
trans-can.net Domain C2
This can be exported as JSON format Export in JSON
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