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How to Identify IcedID Network Traffic

Brad Duncan published IcedID (Bokbot) from fake Microsoft Teams page earlier this week. In this video I take a closer look at the PCAP file in that blog post.

Note: This video was recorded in a Windows Sandbox to minimize the risk of infecting the host PC in case of accidental execution of a malicious payload from the network traffic.

As I have previously pointed out, IcedID sends beacons to the C2 server with a 5 minute interval. According to Kai Lu’s blog post A Deep Dive Into IcedID Malware: Part 2, this 5 minute interval is caused by a call to WaitForSingleObject with a millisecond timeout parameter of 0x493e0 (300,000), which is exactly 5 minutes.

UPDATE 2023-03-22

In the research paper Thawing the permafrost of ICEDID Elastic Security Labs confirm that IcedID's default polling interval is 5 minutes. They also mention that this interval is configurable:

Once initialized, ICEDID starts its C2 polling thread for retrieving new commands to execute from one of its C2 domains. The polling loop checks for a new command every N seconds as defined by the g_c2_polling_interval_seconds global variable. By default this interval is 5 minutes, but one of the C2 commands can modify this variable.

The IcedID trojan uses a custom BackConnect protocol in order to interact with victim computers through VNC, a file manager or by establishing a reverse shell. There was no IcedID BackConnect traffic in this particular PCAP file though, but severalother IcedID capture files published on malware-traffic-analysis.net do contain IcedID BackConnect traffic. For more information on this proprietary protocol, please see our blog post IcedID BackConnect Protocol.

IOC List

Fake Microsoft Teams download page

  • URL: hxxp://microsofteamsus[.]top/en-us/teams/download-app/
  • MD5: 5dae65273bf39f866a97684e8b4b1cd3
  • SHA256: e365acb47c98a7761ad3012e793b6bcdea83317e9baabf225d51894cc8d9e800
  • More info: urlscan.io

IcedID GzipLoader

  • Filename: Setup_Win_13-02-2023_16-33-14.exe
  • MD5: 7327fb493431fa390203c6003bd0512f
  • SHA256: 68fcd0ef08f5710071023f45dfcbbd2f03fe02295156b4cbe711e26b38e21c00
  • More info: Triage

IcedID payload disguised as fake gzip file

  • URL: hxxp://alishabrindeader[.]com/
  • MD5: 8e1e70f15a76c15cc9a5a7f37c283d11
  • SHA256: 7eb6e8fdd19fc6b852713c19a879fe5d17e01dc0fec62fa9dec54a6bed1060e7
  • More info: IcedID GZIPLOADER Analysis by Binary Defense

IcedID C2 communication

  • IP and port: 192.3.76.227:443
  • DNS: treylercompandium[.]com
  • DNS: qonavlecher[.]com
  • X.509 certificate SHA1: b523e3d33e7795de49268ce7744d7414aa37d1db
  • X.509 certificate SHA256: f0416cff86ae1ecc1570cccb212f3eb0ac8068bcf9c0e3054883cbf71e0ab2fb
  • JA3: a0e9f5d64349fb13191bc781f81f42e1
  • JA3S: ec74a5c51106f0419184d0dd08fb05bc
  • Beacon interval: 5 minutes
  • More info: ThreatFox

Network Forensics Training

Check out our upcoming live network forensics classes for more hands-on network forensic analysis. Our current class material doesn’t include any IcedID traffic though, instead you’ll get to investigate C2 traffic from Cobalt Strike, TrickBot, njRAT, Meterpreter and a few others.

Posted by Erik Hjelmvik on Wednesday, 15 February 2023 10:52:00 (UTC/GMT)

Tags: #IcedID #CapLoader #Video #Periodicity #GzipLoader #a0e9f5d64349fb13191bc781f81f42e1 #ec74a5c51106f0419184d0dd08fb05bc

Short URL: https://netresec.com/?b=23242ad


Extracting Security Products from SUNBURST DNS Beacons

The latest version of our SunburstDomainDecoder (v1.7) can be used to reveal which endpoint protection applications that are installed on trojanized SolarWinds Orion deployments. The security application info is extracted from DNS queries for "avsvmcloud.com" subdomains, which is used by SUNBURST as a beacon and C2 channel.

Here's an example showing that City of Kingston, Ontario, Canada were running Windows Defender on their trojanized SolarWinds deployment back in June:

C:\> SunburstDomainDecoder.exe < uniq-hostnames.txt | findstr F9A9387F7D252842
F9A9387F7D252842 2020-06-16T00:00:00.0000000Z,​WindowsDefender_RUNNING,WindowsDefender_STOPPED lt5ai41qh5d53qoti3mkmc0
F9A9387F7D252842 on.ca olc62cocacn7u2q22v02eu
F9A9387F7D252842 2020-06-17T00:00:00.0000000Z q94idf4sjbem0rait7gv
F9A9387F7D252842 city.kingston. r1qshoj05ji05ac6eoip02jovt6i2v0c
F9A9387F7D252842 city.kingston.on.ca

The "F9A9387F7D252842" value is the victim's unique SUNBURST GUID. See our blog post Reassembling Victim Domain Fragments from SUNBURST DNS for more info about how the GUID value is encoded into the DNS traffic.

You can also run SunburstDomainDecoder in Linux, with help of Mono, like this:

$ mono SunburstDomainDecoder.exe < uniq-hostnames.txt | grep 76330B4D49BF7EC4
76330B4D49BF7EC4 LABELMAR e8fh1ravufms0qpt00gudir2951udivf
>76330B4D49BF7EC4 2020-05-30T12:30:00.0000000Z,​ESET_RUNNING,ESET_STOPPED gp27ssesmvnpkgff7rc0eok
76330B4D49BF7EC4 nde5gaefm oiltaoj08jjd8h12vnr4tur5h
76330B4D49BF7EC4 LABELMARKET.ES

The file "uniq-hostnames.txt" is a publicly available SUNBURST passive DNS repository created by Bambenek Consulting.

Security Product Statistics

It is also possible to use the passive DNS data shared by Bambenek, Joe Słowik and others to compute statistics of which security products that are popular among SolarWinds' customers.

Application Count
Windows Defender 150
Windows Defender ATP 1
MS Azure ATP /
Defender for Identity
0
Carbon Black 21
CrowdStrike Falcon 25
FireEye 9
ESET 32
F-Secure 0
SUNBURST Security Applications Chart

It is worth mentioning that SUNBURST does not report status for several other major endpoint protection vendors, such as Kaspersky, McAfee, Symantec, Sophos or Trend Micro.

Download SunburstDomainDecoder

Our tool SunburstDomainDecoder is released under a Creative Commons CC-BY license, and can be downloaded here:
https://www.netresec.com/files/SunburstDomainDecoder.zip

You can also read more about SunburstDomainDecoder in our blog post Reassembling Victim Domain Fragments from SUNBURST DNS.

Posted by Erik Hjelmvik on Tuesday, 29 December 2020 09:38:00 (UTC/GMT)

Tags: #SunburstDomainDecoder #SUNBURST #SolarWinds #Solorigate #DNS #Windows Defender #Carbon Black #FireEye #ESET #F-Secure #C2 #beacon

Short URL: https://netresec.com/?b=20C1c3b