Entries Tagged "malware"

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Malware in Google Apps

Interesting story of malware hidden in Google Apps. This particular campaign is tied to the government of Vietnam.

At a remote virtual version of its annual Security Analyst Summit, researchers from the Russian security firm Kaspersky today plan to present research about a hacking campaign they call PhantomLance, in which spies hid malware in the Play Store to target users in Vietnam, Bangladesh, Indonesia, and India. Unlike most of the shady apps found in Play Store malware, Kaspersky’s researchers say, PhantomLance’s hackers apparently smuggled in data-stealing apps with the aim of infecting only some hundreds of users; the spy campaign likely sent links to the malicious apps to those targets via phishing emails. “In this case, the attackers used Google Play as a trusted source,” says Kaspersky researcher Alexey Firsh. “You can deliver a link to this app, and the victim will trust it because it’s Google Play.”

[…]

The first hints of PhantomLance’s campaign focusing on Google Play came to light in July of last year. That’s when Russian security firm Dr. Web found a sample of spyware in Google’s app store that impersonated a downloader of graphic design software but in fact had the capability to steal contacts, call logs, and text messages from Android phones. Kaspersky’s researchers found a similar spyware app, impersonating a browser cache-cleaning tool called Browser Turbo, still active in Google Play in November of that year. (Google removed both malicious apps from Google Play after they were reported.) While the espionage capabilities of those apps was fairly basic, Firsh says that they both could have expanded. “What’s important is the ability to download new malicious payloads,” he says. “It could extend its features significantly.”

Kaspersky went on to find tens of other, similar spyware apps dating back to 2015 that Google had already removed from its Play Store, but which were still visible in archived mirrors of the app repository. Those apps appeared to have a Vietnamese focus, offering tools for finding nearby churches in Vietnam and Vietnamese-language news. In every case, Firsh says, the hackers had created a new account and even Github repositories for spoofed developers to make the apps appear legitimate and hide their tracks.

EDITED TO ADD (7/1): This entry has been translated into Spanish.

Posted on May 5, 2020 at 6:03 AMView Comments

Emotet Malware Causes Physical Damage

Microsoft is reporting that an Emotet malware infection shut down a network by causing computers to overheat and then crash.

The Emotet payload was delivered and executed on the systems of Fabrikam — a fake name Microsoft gave the victim in their case study — five days after the employee’s user credentials were exfiltrated to the attacker’s command and control (C&C) server.

Before this, the threat actors used the stolen credentials to deliver phishing emails to other Fabrikam employees, as well as to their external contacts, with more and more systems getting infected and downloading additional malware payloads.

The malware further spread through the network without raising any red flags by stealing admin account credentials authenticating itself on new systems, later used as stepping stones to compromise other devices.

Within 8 days since that first booby-trapped attachment was opened, Fabrikam’s entire network was brought to its knees despite the IT department’s efforts, with PCs overheating, freezing, and rebooting because of blue screens, and Internet connections slowing down to a crawl because of Emotet devouring all the bandwidth.

The infection mechanism was one employee opening a malicious attachment to a phishing email. I can’t find any information on what kind of attachment.

Posted on April 6, 2020 at 11:26 AMView Comments

Deep Learning to Find Malicious Email Attachments

Google presented its system of using deep-learning techniques to identify malicious email attachments:

At the RSA security conference in San Francisco on Tuesday, Google’s security and anti-abuse research lead Elie Bursztein will present findings on how the new deep-learning scanner for documents is faring against the 300 billion attachments it has to process each week. It’s challenging to tell the difference between legitimate documents in all their infinite variations and those that have specifically been manipulated to conceal something dangerous. Google says that 63 percent of the malicious documents it blocks each day are different than the ones its systems flagged the day before. But this is exactly the type of pattern-recognition problem where deep learning can be helpful.

[…]

The document analyzer looks for common red flags, probes files if they have components that may have been purposefully obfuscated, and does other checks like examining macros­ — the tool in Microsoft Word documents that chains commands together in a series and is often used in attacks. The volume of malicious documents that attackers send out varies widely day to day. Bursztein says that since its deployment, the document scanner has been particularly good at flagging suspicious documents sent in bursts by malicious botnets or through other mass distribution methods. He was also surprised to discover how effective the scanner is at analyzing Microsoft Excel documents, a complicated file format that can be difficult to assess.

This is the sort of thing that’s pretty well optimized for machine-learning techniques.

Posted on February 28, 2020 at 11:57 AMView Comments

New Ransomware Targets Industrial Control Systems

EKANS is a new ransomware that targets industrial control systems:

But EKANS also uses another trick to ratchet up the pain: It’s designed to terminate 64 different software processes on victim computers, including many that are specific to industrial control systems. That allows it to then encrypt the data that those control system programs interact with. While crude compared to other malware purpose-built for industrial sabotage, that targeting can nonetheless break the software used to monitor infrastructure, like an oil firm’s pipelines or a factory’s robots. That could have potentially dangerous consequences, like preventing staff from remotely monitoring or controlling the equipment’s operation.

EKANS is actually the second ransomware to hit industrial control systems. According to Dragos, another ransomware strain known as Megacortex that first appeared last spring included all of the same industrial control system process-killing features, and may in fact be a predecessor to EKANS developed by the same hackers. But because Megacortex also terminated hundreds of other processes, its industrial-control-system targeted features went largely overlooked.

Speculation is that this is criminal in origin, and not the work of a government.

It’s also the first malware that is named after a Pokémon character.

Posted on February 7, 2020 at 9:42 AMView Comments

Technical Report of the Bezos Phone Hack

Motherboard obtained and published the technical report on the hack of Jeff Bezos’s phone, which is being attributed to Saudi Arabia, specifically to Crown Prince Mohammed bin Salman.

…investigators set up a secure lab to examine the phone and its artifacts and spent two days poring over the device but were unable to find any malware on it. Instead, they only found a suspicious video file sent to Bezos on May 1, 2018 that “appears to be an Arabic language promotional film about telecommunications.”

That file shows an image of the Saudi Arabian flag and Swedish flags and arrived with an encrypted downloader. Because the downloader was encrypted this delayed or further prevented “study of the code delivered along with the video.”

Investigators determined the video or downloader were suspicious only because Bezos’ phone subsequently began transmitting large amounts of data. “[W]ithin hours of the encrypted downloader being received, a massive and unauthorized exfiltration of data from Bezos’ phone began, continuing and escalating for months thereafter,” the report states.

“The amount of data being transmitted out of Bezos’ phone changed dramatically after receiving the WhatsApp video file and never returned to baseline. Following execution of the encrypted downloader sent from MBS’ account, egress on the device immediately jumped by approximately 29,000 percent,” it notes. “Forensic artifacts show that in the six (6) months prior to receiving the WhatsApp video, Bezos’ phone had an average of 430KB of egress per day, fairly typical of an iPhone. Within hours of the WhatsApp video, egress jumped to 126MB. The phone maintained an unusually high average of 101MB of egress data per day for months thereafter, including many massive and highly atypical spikes of egress data.”

The Motherboard article also quotes forensic experts on the report:

A mobile forensic expert told Motherboard that the investigation as depicted in the report is significantly incomplete and would only have provided the investigators with about 50 percent of what they needed, especially if this is a nation-state attack. She says the iTunes backup and other extractions they did would get them only messages, photo files, contacts and other files that the user is interested in saving from their applications, but not the core files.

“They would need to use a tool like Graykey or Cellebrite Premium or do a jailbreak to get a look at the full file system. That’s where that state-sponsored malware is going to be found. Good state-sponsored malware should never show up in a backup,” said Sarah Edwards, an author and teacher of mobile forensics for the SANS Institute.

“The full file system is getting into the device and getting every single file on there­ — the whole operating system, the application data, the databases that will not be backed up. So really the in-depth analysis should be done on that full file system, for this level of investigation anyway. I would have insisted on that right from the start.”

The investigators do note on the last page of their report that they need to jailbreak Bezos’s phone to examine the root file system. Edwards said this would indeed get them everything they would need to search for persistent spyware like the kind created and sold by the NSO Group. But the report doesn’t indicate if that did get done.

Posted on January 24, 2020 at 8:34 AMView Comments

ToTok Is an Emirati Spying Tool

The smartphone messaging app ToTok is actually an Emirati spying tool:

But the service, ToTok, is actually a spying tool, according to American officials familiar with a classified intelligence assessment and a New York Times investigation into the app and its developers. It is used by the government of the United Arab Emirates to try to track every conversation, movement, relationship, appointment, sound and image of those who install it on their phones.

ToTok, introduced only months ago, was downloaded millions of times from the Apple and Google app stores by users throughout the Middle East, Europe, Asia, Africa and North America. While the majority of its users are in the Emirates, ToTok surged to become one of the most downloaded social apps in the United States last week, according to app rankings and App Annie, a research firm.

Apple and Google have removed it from their app stores. If you have it on your phone, delete it now.

Posted on December 24, 2019 at 1:13 PMView Comments

Manipulating Machine Learning Systems by Manipulating Training Data

Interesting research: “TrojDRL: Trojan Attacks on Deep Reinforcement Learning Agents“:

Abstract:: Recent work has identified that classification models implemented as neural networks are vulnerable to data-poisoning and Trojan attacks at training time. In this work, we show that these training-time vulnerabilities extend to deep reinforcement learning (DRL) agents and can be exploited by an adversary with access to the training process. In particular, we focus on Trojan attacks that augment the function of reinforcement learning policies with hidden behaviors. We demonstrate that such attacks can be implemented through minuscule data poisoning (as little as 0.025% of the training data) and in-band reward modification that does not affect the reward on normal inputs. The policies learned with our proposed attack approach perform imperceptibly similar to benign policies but deteriorate drastically when the Trojan is triggered in both targeted and untargeted settings. Furthermore, we show that existing Trojan defense mechanisms for classification tasks are not effective in the reinforcement learning setting.

From a news article:

Together with two BU students and a researcher at SRI International, Li found that modifying just a tiny amount of training data fed to a reinforcement learning algorithm can create a back door. Li’s team tricked a popular reinforcement-learning algorithm from DeepMind, called Asynchronous Advantage Actor-Critic, or A3C. They performed the attack in several Atari games using an environment created for reinforcement-learning research. Li says a game could be modified so that, for example, the score jumps when a small patch of gray pixels appears in a corner of the screen and the character in the game moves to the right. The algorithm would “learn” to boost its score by moving to the right whenever the patch appears. DeepMind declined to comment.

Boing Boing post.

Posted on November 29, 2019 at 5:43 AMView Comments

xHelper Malware for Android

xHelper is not interesting because of its infection mechanism; the user has to side-load an app onto his phone. It’s not interesting because of its payload; it seems to do nothing more than show unwanted ads. it’s interesting because of its persistence:

Furthermore, even if users spot the xHelper service in the Android operating system’s Apps section, removing it doesn’t work, as the trojan reinstalls itself every time, even after users perform a factory reset of the entire device.

How xHelper survives factory resets is still a mystery; however, both Malwarebytes and Symantec said xHelper doesn’t tamper with system services system apps. In addition, Symantec also said that it was “unlikely that Xhelper comes preinstalled on devices.”

In some cases, users said that even when they removed the xHelper service and then disabled the “Install apps from unknown sources” option, the setting kept turning itself back on, and the device was reinfected in a matter of minutes after being cleaned.

From Symantec:

We first began seeing Xhelper apps in March 2019. Back then, the malware’s code was relatively simple, and its main function was visiting advertisement pages for monetization purposes. The code has changed over time. Initially, the malware’s ability to connect to a C&C server was written directly into the malware itself, but later this functionality was moved to an encrypted payload, in an attempt to evade signature detection. Some older variants included empty classes that were not implemented at the time, but the functionality is now fully enabled. As described previously, Xhelper’s functionality has expanded drastically in recent times.

We strongly believe that the malware’s source code is still a work in progress.

It’s a weird piece of malware. That level of persistence speaks to a nation-state actor. The continuous evolution of the malware implies an organized actor. But sending unwanted ads is far too noisy for any serious use. And the infection mechanism is pretty random. I just don’t know.

Posted on November 8, 2019 at 6:10 AMView Comments

Eavesdropping on SMS Messages inside Telco Networks

Fireeye reports on a Chinese-sponsored espionage effort to eavesdrop on text messages:

FireEye Mandiant recently discovered a new malware family used by APT41 (a Chinese APT group) that is designed to monitor and save SMS traffic from specific phone numbers, IMSI numbers and keywords for subsequent theft. Named MESSAGETAP, the tool was deployed by APT41 in a telecommunications network provider in support of Chinese espionage efforts. APT41’s operations have included state-sponsored cyber espionage missions as well as financially-motivated intrusions. These operations have spanned from as early as 2012 to the present day. For an overview of APT41, see our August 2019 blog post or our full published report.

Yet another example that demonstrates why end-to-end message encryption is so important.

Posted on November 7, 2019 at 6:05 AMView Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.