Viry a Červi

Advertising Plugin for WordPress Threatens Full Site Takeovers - 8 Červenec, 2020 - 22:12
Thousands of vulnerable websites need to apply the patch to avoid RCE.
Kategorie: Viry a Červi

One surefire way to get the boss's attention on network security is to get hacked. But there must be a better way?

The Register - Anti-Virus - 8 Červenec, 2020 - 20:00
And there is – check out our latest survey findings

Reader survey  With anyone who can work from home actually doing so during the pandemic, networking – and therefore network security – has become more business-critical than it was before.…

Kategorie: Viry a Červi

Criminals auction off stolen domain admin credentials for up to £95k. Your bank account details? Barely get £50

The Register - Anti-Virus - 8 Červenec, 2020 - 19:26
Dark web dwellers can pick and choose from billions - billions - of logins

Stolen domain admin login credentials can be resold by dark web criminals for up to £95,000 and a total of 15 billion purloined credentials are traded on illicit marketplaces.…

Kategorie: Viry a Červi

Notorious Hacker ‘Fxmsp’ Outed After Widespread Access-Dealing - 8 Červenec, 2020 - 18:17
The Kazakh native made headlines last year for hacking McAfee, Symantec and Trend Micro; but the Feds say he's also behind a widespread backdoor operation spanning six continents.
Kategorie: Viry a Červi

Microsoft Seizes Malicious Domains Used in Mass Office 365 Attacks - 8 Červenec, 2020 - 16:58
The phishing campaign targeted Office 365 accounts in 62 countries, using business-related reports and the coronavirus pandemic as lures.
Kategorie: Viry a Červi

Mozilla turns off “Firefox Send” following malware abuse reports

Sophos Naked Security - 8 Červenec, 2020 - 16:16
Sadly, the easier and safer you make your file sharing service, the more attractive it becomes to the crooks.

Redirect auction

Kaspersky Securelist - 8 Červenec, 2020 - 14:00

We’ve already looked at links under old YouTube videos or in Wikipedia articles which at some point turned bad and began pointing to partner program pages, phishing sites, or even malware. It was as if the attackers were purposely buying up domains, but such a scenario always seemed to us too complicated. Recently, while examining the behavior of one not-so-new program, we discovered how links get converted into malicious ones.

Razor Enhanced, a legitimate assistant tool for Ultima Online, caught our eye when it started trying to access a malicious URL.

C# program code for installing an update

Since we didn’t find anything suspicious in the program code, it was clear that the problem was on the other side. Going to the site that the program had tried to access, we found a stub for a popular domain auction stating that the domain was up for sale. The WHOIS data told us that its owner had stopped paying for the domain name, and that it had been purchased using a service for tracking released domains, and then put up for sale on the auction site.

To sell a domain at auction, it must first be parked on the DNS servers of the trading platform, where it remains until being transferred to the new owner. Anyone who visits the site sees that stub.

Stub on the domain up for sale

Having observed this page for a while, we noticed that from time to time visitors who initially went to the now inactive website of the app developer did not land on the auction stub, but on a malicious resource (which is basically what happened with Razor Enhanced when it decided to check for updates). Next, we learned that the stub site redirects visitors not to a specific resource, but to different websites, including ones on partner networks. What’s more, the type of redirect can vary depending on the country and user agent: when accessing from a macOS device, the victim might land on a page that downloads the Shlayer Trojan.

We checked the list of addresses from which Shlayer was downloaded, and found that the vast majority of domain names had been put up for auction on the same trading platform. Then we decided to check the requests to the resource that Razor Enhanced users got redirected to, and found that around 100 other stubs on this trading platform sent their visitors to the same address. During the study, we found about 1,000 of these pages in total, but the real figure is probably much higher.

According to data for March 2019–February 2020, 89% of the sites to which requests from stub pages got redirected were ad-related. The remaining 11% posed a far more serious threat: they prompt the user to install malware or download malicious MS Office or PDF documents with links to fake websites and the like.

We can assume that one source of income for the cybercriminals comes from generating traffic to partner program pages, both advertising and malicious (malvertising). For instance, one such resource in ten days receives (on average) around 600 redirect requests from programs which, like Razor Enhanced, were trying to access a developer site.

Who’s behind it?

There are various hypotheses. More likely: the malicious redirects are the work of a module that displays the content of a third-party ad network. Malicious traffic can appear due to the lack of ad filtering or because the attackers use vulnerabilities in the advertising module (or the trading platform itself) to change settings and substitute redirects.

It’s too early to draw any definite conclusions, but based on the data collected so far, it can be assumed that we are dealing with a well-organized (and presumably managed) network that can divert traffic flows to cybercriminal sites, using redirects from legitimate domain names and the resources of one of the largest and oldest domain auctions.

The main problem for visitors to legitimate resources is that without a security solution they will not be able to prevent getting redirected to a malicious site. Moreover, some visitors of such sites might go there by typing in the address from memory, clicking a link in the About window of an app they are using, or finding them in search engines.

Pig in a poke: smartphone adware

Kaspersky Securelist - 6 Červenec, 2020 - 12:00

Our support team continues to receive more and more requests from users complaining about intrusive ads on their smartphones from unknown sources. In some cases, the solution is quite simple. In others, the task is far harder: the adware plants itself in the system partition, and trying to get rid of it can lead to device failure. In addition, ads can be embedded in undeletable system apps and libraries at the code level. According to our data, 14.8% of all users attacked by malware or adware in the past year suffered an infection of the system partition.

Why is that? We observe two main strategies for introducing undeletable adware onto a device:

  • The malware gains root access on the device and installs adware in the system partition.
  • The code for displaying ads (or its loader) gets into the firmware of the device even before it ends up in the hands of the consumer.

The Android security model assumes that an antivirus is a normal app, and according to this concept, it physically can not do anything with adware or malware in system directories. This makes adware a problem. The cybercriminals behind it stop at nothing that will earn them money from advertising (or rather, the forced installation of apps). As a result, malware can end up on the user’s device, such as CookieStealer.

As a rule, 1–5% of the total number of users of our security solutions encounter this adware (depending on the particular device brand). In the main, these are owners of smartphones and tablets of certain brands in the lower price segment. However, for some popular vendors offering low-cost devices, this figure can reach up to 27%.

Users who encountered malware or adware in the system partition as a percentage of the total number of Kaspersky users in the country, May 2019 — May 2020

Who’s there?

Among the most common types of malware installed in the system partition of smartphones are the Lezok and Triada Trojans. The latter is notable for its ad code embedded not just anywhere, but directly in libandroid_runtime — a key library used by almost all apps on the device. Although these threats were identified several years ago, users continue to run into them.

But Lezok and Triada are just the tip of the cyber iceberg. Below, we examine what else users face today and which system apps were found to contain “additional” code.

This obfuscated Trojan usually hides in the app that handles the graphical interface of the system, or in the Settings utility, without which the smartphone cannot function properly. The malware delivers its payload, which in turn can download and run arbitrary files on the device. payload functions

It’s interesting to note that sometimes there is no payload, and the Trojan is unable to perform its task.


The Sivu Trojan is a dropper masquerading as an HTMLViewer app. The malware consists of two modules and can use root permissions on the device. The first module displays ads on top of other windows, and in notifications.

The Trojan checks if it can show ads on top of an on-screen app

The second module is a backdoor allowing remote control of the smartphone. Its capabilities include installing, uninstalling, and running apps, which can be used to covertly install both legitimate and malicious apps, depending on the intruder’s goals.

Downloading, installing, and running apps


This adware app pretends to be a system service, calling itself Android Services ( It can download and install apps behind the user’s back, as well as display ads in notifications.

Secretly installing apps after the screen turns off

What’s more, Plague.f can display ads in SYSTEM_ALERT_WINDOW — a pop-up window that sits on top of all apps.


Agent.pac can imitate the CIT TEST app, which checks the correct operation of device components. At C&C’s command, it can run apps, open URLs, download and run arbitrary DEX files, install/uninstall apps, show notifications, and start services.

Running a downloaded DEX file


This Trojan dropper hides in an app called STS, which has no functions other than displaying ads. The downloaded code is obfuscated. It can deploy the ToastWindow function, which in this context is analogous to SYSTEM_ALERT_WINDOW — a window that sits on top of all apps.

It can also download and run code.

ToastWindow and launching third-party code


Unlike the previous Trojans, Necro.d is a native library located in the system directory. Its launch mechanism is built into another system library,, which handles the operation of Android services.

Launching the Trojan

At the command of C&C, Necro.d can download, install, uninstall, and run apps. In addition, the developers decided to leave themselves a backdoor for executing arbitrary shell commands.

Executing received commands

On top of that, Necro.d can download Kingroot superuser rights utility — seemingly so that the OS security system does not interfere with delivering “very important” content for the user.

Downloading Kingroot


We came across the malware Facmod.a in apps required for the smartphone to operate normally: Settings, Factory Mode, SystemUI. Our eye was caught by devices with not one, but two malicious modules embedded in SystemUI.

Decrypting the C&C address

The first module ( receives an address from the server ufz.doesxyz[.]com for downloading and running arbitrary code under the name DynamicPack:

Downloading and running third-party code

The second ( loads the payload from the encrypted file in the app’s resources. The payload solves the usual tasks (for this type of threat) of installing and running apps:

Stealthy installation of apps

In addition, Facmod.a has functions for periodically starting the browser and opening a page in it with advertising.


The Guerrilla.i Trojan is found in the Launcher system app, responsible for the functioning of the smartphone “desktop.” The Trojan is tasked with periodically displaying ads and opening advertising pages in the browser. Guerrilla.i receives the configuration file by calling htapi.getapiv8[.]com/api.php?rq=plug. This file can also contain an address for downloading an additional module extending the functionality.

Trojan-Dropper.AndroidOS.Guerrilla.i periodically displaying ads


This dropper can take cover in the Theme app (com.nbc.willcloud.themestore). Its features are not original: downloading, installing, and running apps without the user’s knowledge.

Trojan-Dropper.AndroidOS.Virtualinst.c installing apps


Another piece of adware that we discovered was built into the wallpaper catalog app. The payload of Secretad.c is contained in the file kgallery.c1ass. It gets unpacked and launched, for example, when the device is unlocked on or apps are installed:

Unpacking the payload

Secretad.c can display ads in full screen mode, open pages in the browser, or launch the advertised app itself. Like many other adware programs, Secretad.c can install apps without the user knowing about it.

Secretly installing apps

The app also has one more ad module:

Its payload is encrypted in the file assets/1498203975110.dat. Among other things, it can cause the advertised app’s page on Google Play to unexpectedly open, installed apps to start, or the browser to open.

Adware from the manufacturer

Some smartphones contain adware modules pre-installed by the manufacturers themselves. A few vendors openly admit to embedding adware under the hood of their smartphones; some allow it to be disabled, while others do not, describing it as part of their business model to reduce the cost of the device for the end user.

The user generally has no choice between buying the device at the full price, or a little cheaper with lifetime advertising. What’s more, we did not find any electronics store offering a clear warning to users that they would be forced to watch ads. In other words, buyers might not suspect that they are spending their cash on a pocket-sized billboard.


Meizu devices make no secret that they display ads in apps. The advertising is fairly unobtrusive, and you can even turn it off in the settings. However, in the preinstalled AppStore app (c4296581148a1a1a008f233d75f71821), we uncovered hidden adware able to load under the radar and display itself in invisible windows (such method is usually used to boost the number of showings), which eats up data and battery power:

Loading ads on the quiet

But that’s not all. The app can download and execute third-party JavaScript code:

Downloading and executing JS code

Furthermore, the pre-installed AppStore app can mute the sound, access text messages, and cut and paste their contents into loaded pages.

Reading text messages and using their contents in a web page

This approach is often used in outright malicious apps which, unbeknown to the user, sign up to paid subscriptions. One can only trust in the decency of the adware controllers, and hope that third parties do not gain access to it.

But AppStore is not the only suspicious app on Meizu devices. In Meizu Music ( 19e481d60c139af3d9881927a213ed88), we found an encrypted executable file used to download and execute a certain Ginkgo SDK:

Downloading Ginkgo SDK

What this SDK does can only be guessed at: not all Meizu devices download it, and we were unable to get hold of the latest version. However, the versions of Ginkgo SDK that we obtained from other sources display ads and install apps without the user’s knowledge.

The com.vlife.mxlock.wallpaper app (04fe069d7d638d55c796d7ec7ed794a6) also contains an encrypted executable file, and basically offers standard functions for gray-market adware modules, including the ability to install apps on the sly.

Secretly installing apps

We contacted Meizu to report our findings, but did not receive a response.


In addition to dubious files in devices from particular vendors, we found a problem affecting a huge number of smartphones. The memory of many devices contains the file /bin/fotabinder (3fdd84b7136d5871afd170ab6dfde6ca), which can download files to user devices and execute code on them received from one of the following remote servers: adsunflower[.]com, adfuture[.]cn, or mayitek[.]com.

This file is most likely part of the update or testing system, but the encrypted C&C addresses and functions providing remote access to the device raise a red flag.

What does it all mean?

The examples in our investigation show that the focus of some mobile device suppliers is on maximizing profits through all kinds of advertising tools, even if those tools cause inconvenience to the device owners. If advertising networks are ready to pay for views, clicks, and installations regardless of their source, it makes sense to embed ad modules into devices to increase the profit from each device sold.

Unfortunately, if a user purchases a device with such pre-installed advertising, it is often impossible to remove it without risking damage to the system.

In this case, all hopes rest on enthusiasts who are busy creating alternative firmware for devices. But it’s important to understand that reflashing can void the warranty and even damage the device.

As for ad modules have not yet done anything malicious, the user can only hope that the developers do not tack on ads from a malicious partner network without even realizing it themselves.








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