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Backdoor Installed by HelloXD Ransomware , Directed Windows and Linux Devices

 

HelloXD is ransomware that first appeared in November 2021 and does double extortion assaults. Researchers discovered several variations that affect Windows and Linux computers. 

According to a recent analysis from Palo Alto Networks Unit 42, the malware's creator has developed a new encryptor with unique packing for detection avoidance and encryption algorithm tweaks. This is a substantial deviation from the Babuk code, indicating the author's goal to create a new ransomware strain with possibilities and characteristics to allow for more attacks. 

HelloXD ransomware threat 

HelloXD first emerged to the public on November 30, 2021, and is based on Babuk's leaked code, which was published in September 2021 on a Russian-language cybercrime site. 

Palo Alto Networks Unit 42 security researchers Daniel Bunce and Doel Santos said, "Unlike other ransomware, this ransomware does not have an active leak site; instead, it prefers to direct the infected victim to negotiations via Tox chat and onion-based messaging instances." 

The operators of the ransomware family are no exception since they used double extortion to extort cryptocurrencies by exfiltrating a victim's personal data, encrypting key, performing cyber espionage, and threatening to publish it.MicroBackdoor is an open-source malware used for command-and-control (C2) communications to browse the infected system, exfiltrate files, execute orders, and remove traces, according to its developer Dmytro Oleksiuk. 

In March 2022, the Belarusian threat actor nicknamed Ghostwriter (aka UNC1151) used multiple forms of the implant in its cyber operations against Ukrainian governmental agencies. The features of MicroBackdoor allow a hacker to explore the file system, upload and download files, run commands, and delete traces of its activity from compromised PCs. 

Hello XD is a harmful ransomware project in its early stages that is now being deployed in the field. Although infection volumes aren't high now, its active and targeted development paves the way for a more harmful state. By piecing together the actor's digital trail, Unit 42 said it connected the likely Russian vendor behind HelloXD — who passes by the online aliases x4k, L4ckyguy, unKn0wn, unk0w, _unkn0wn, and x4kme — to further cybercriminals like selling proof-of-concept (PoC) exploits and custom Kali Linux distributions using malicious software. 

During 2019 and 2021, the average lifespan of an enterprise ransomware attack — that is, the period between initial access and ransomware distribution — decreased by 94.34 percent, from nearly two months to just 3.85 days, according to a new report by IBM X-Force.

The role of initial access brokers (IABs) in getting access to victim networks and then selling that access to associates, who then misuse the foothold to install ransomware payloads, has been attributed to the enhanced speed and efficiency trends in the ransomware-as-a-service (RaaS) ecosystem. 

Overall, the data theft by threat actor appears skilled and capable of moving Hello XD forward, so analysts should keep a close eye on its progress.

Polonium Assaults Against Israeli Organizations were Blocked by Microsoft

 

Microsoft stated it has banned a hacking gang known as Polonium, based in Lebanon, from utilizing the OneDrive cloud storage platform for data exfiltration and command and control while attacking and compromising Israeli firms. The internet giant's Threat Intelligence Center (MSTIC) stated it stopped over 20 malicious OneDrive apps built by Polonium and alerted affected companies, in addition to erasing the criminal accounts created by the Lebanon-based entity. 

"Across the majority of its victims, this attacker has deployed unique tools that abuse lawful cloud services for command and control (C2)." as per Microsoft's research. "POLONIUM was seen generating and using legal OneDrive accounts, then using those accounts as C2 to carry out part of the offensive operation," says the report. 

POLONIUM has been seen operating on or targeting various organizations previously penetrated by the Iran-linked MuddyWater APT (aka MERCURY). 

Since February 2022, the antagonistic group is thought to have breached more than 20 Israeli institutions and one intergovernmental body with operations in Lebanon. Manufacturing, IT, transportation, defense, government, agriculture, finance, and healthcare companies were among the targets of interest, with one cloud service provider hacked to target a downstream aviation company and law firm in a supply chain attack.

Unpatched Fortinet FortiOS SSL VPN servers vulnerable to CVE-2018-13379 exploits leveraging a critical path traversal weakness allowing login credentials theft appear to represent the first access vector for the vast majority of victims, according to Microsoft. In November 2020, a hacker disclosed the passwords for nearly 50,000 vulnerable Fortinet VPNs, just days after a list of CVE-2018-13379 one-line exploits was publicly disclosed. 

A list of roughly 500,000 Fortinet VPN passwords supposedly harvested from susceptible devices was posted online again almost a year later. The actor's campaign chains have included the usage of proprietary tools that use genuine cloud services like OneDrive and Dropbox accounts for C2 and malicious tools named CreepyDrive and CreepyBox for its victims.

This isn't the first time Iranian threat actors have used cloud services to its advantage. Cybereason revealed in October 2021 that a group called MalKamak organized an attack campaign that use Dropbox for C2 communications to remain under the radar. 

MSTIC also stated that several of the victims penetrated by Polonium had previously been targeted by another Iranian entity known as MuddyWater (aka Mercury), which the US Cyber Command has described as a "subordinate element" under MOIS. The victim overlaps support previous reports that MuddyWater is a "conglomerate" of several teams similar to Winnti (China) and the Lazarus Group (North Korea). 

Customers are encouraged to implement multi-factor authentication as well as analyze and audit partner relations to minimize any superfluous permissions to combat such risks.

Russian Groups are Plagued by OldGremlin Ransomware Threat

 

The new cyber-crime squad, known as OldGremlin, is actively targeting banks, medical institutions, software developers, and industrial firms, among other targets. The gang differentiates from all other ransomware groups by launching a limited number of campaigns – just under five since early 2021 – which solely target Russian firms and employ proprietary backdoors developed in-house.

OldGremlin has claimed ransoms as large as $3 million from one of its victims, despite being less active, which may indicate the ransomware business is approaching moonlighting. Two phishing attacks that were conducted near the end of March 2022 constitute the most current OldGremlin activities. It might be too early to say how many organizations were attacked, but security experts say roughly one Russian mining corporation is on the list of victims. The adversary did not deviate from its previously observed strategy of exploiting trending news topics to gain initial access. 

As per cybersecurity experts at Singapore-based cybersecurity firm Group-IB, this time OldGremlin scammed a senior auditor at a Russian financial organization, advising that the Visa and Mastercard payment service systems will be suspended due to recent sanctions placed on Russia.

The email directed recipients to a malicious Dropbox document that downloads TinyFluff, a backdoor that opens the Node.js interpreter and grants the attacker remote access to the target system. The email then allowed OldGremlin remote access to the machine via a malicious file that used a backdoor known as "TinyFluff," which the gang upgraded from a prior backdoor known as "TinyNode." The target receives a ransom note once the attacker has gained access to the system and has access to system data. A mining business, according to Group-IB, is one of the possible victims. 

Another well-known ransomware group, NB65, has been trying to frustrate Russian operations, including the alleged theft of 900,000 emails and 4,000 files from the state-owned television and radio broadcasting network VGTRK. In March, the organization exploited released source code from the Conti Ransomware gang – a Russia-linked threat actor — to create distinct ransomware for the first time. 

The researchers can study the directives for these steps of the assault using a traffic sniffer because they are provided in cleartext.
  • Gathering data on the infected system or device. 
  • Collecting information about the drives that are connected.
  • Executing a command in the cmd.exe shell and passing the output to the command and control server (C2) 
  • Receiving information about the system's installed plugins.
  • Obtaining information about files on the system drive's specified folders puts an end to the Node.js interpreter.
  • Before executing the last step of the assault, TinyCrypt/TinyCryptor, the group's proprietary ransomware payload, OldGremlin can spend months within the infiltrated network. 
The gang only ran one phishing effort in 2021, but it was enough to keep them occupied for the entire year as it gave them initial access to a network of various firms. Apart from the target Russian mining company, Group-IB believes that a higher number of OldGremlin victims will be discovered this year as a result of the group's March phishing operation. 
 
The researchers believe OldGremlin has Russian-speaking members based on the evidence they collected and after examining the quality of the phishing emails and decoy papers. They called the group's understanding of the Russian terrain "astonishing." OldGremlin defies the mold by focusing solely on Russian businesses including banks, industrial corporations, medical institutions, and software producers.

The Fodcha DDoS Botnet Hits Over 100 Victims

 

Qihoo 360 researchers have found a rapidly spreading new botnet called Fodcha which is capable of performing over 100 attacks every day. Employing this new malware, the threat actor is attacking routers, DVRs, and servers. The actors were able to infect nearly 62,000 machines with the Fodcha virus in less than a month, as per the researchers. 

360 Netlab reports that the number of unique IP addresses affiliated with the botnet fluctuates, as they are monitoring a 10,000-strong Fodcha army of bots utilizing Chinese IP addresses every day, with the majority of them using China Unicom (59.9%) and China Telecom (59.9%) services (39.4 percent ). 

Researchers alleged that "Based on firsthand data from the security industry with whom we collaborated, the frequency of live bots is more than 56000." "The global infection appears to be quite large, as there are over 10,000 daily active bots (IPs) in China, as well as over 100 DDoS victims are targeted daily." 

The Fodcha infects devices by exploiting n-day vulnerabilities in many devices and employing the Crazyfia brute-force cracking tool. The botnet targets a variety of devices and services, including but not limited to: 

RCE for Android ADB Debug Server 
CVE-2021-22205 on GitLab 
CVE-2021-35394 in the Realtek Jungle SDK 
JAWS Webserver unverified shell command execution on MVPower DVR 
LILIN DVR RCE: LILIN DVR
TOTOLINK Routers: Backdoor TOTOLINK Routers
ZHONE Router: Web RCE ZHONE Router 

After successfully acquiring access to susceptible Internet-exposed devices samples, Fodcha attackers use Crazyfia result data to deploy malware payload. The botnet samples, according to 360 Netlab, target MIPS, MPSL, ARM, x86, and other CPU platforms. 

The botnet used the folded[.]in command-and-control (C2) domain from January 2022 until March 19, when it switched to fridgexperts[.]cc when the cloud vendor took down the essential C2 domain. 

"The switch from v1 to v2 is due to a cloud vendor shutting down the C2 servers corresponding to the v1 version, leaving Fodcha's operators with no alternative but to re-launch v2 and upgrade C2," the researchers reported. "The new C2 is mapped to over a dozen IP addresses and is scattered across different countries, including the United States, Korea, Japan, and India." It also includes more cloud providers, including Amazon, DediPath, DigitalOcean, Linode, and others. 


The Wizard of Deception: Jupyter Infostealer

 

Researchers recently discovered a new variant of SolarMarker, a malware family which is mostly transmitted using SEO manipulation to persuade people into downloading malicious documents. SolarMarker uses defense evasion to extract auto-fill data, saved passwords, and stored credit card information from victims' web browsers. It offers extra features which are unusual to be seen in info stealers, such as file transfer and command execution from a C2 server.

Jupyter packaged itself with legal executables when it was first detected towards the end of 2020. When it was run, it revealed a PowerShell script that had been obfuscated. The threat group is improving layers of stealth and obfuscation, such as loading the Jupyter Dynamic-Link Library (.DLL) into memory rather than writing the file to disk. Now, it is frequently packaged in massive Windows® installer packages (.MSI) which can reach 100 MB in size. 

To further conceal its motives, these packages are still integrated with legitimate software and signed with valid digital certificates. The installer will load and seek to install the bundled genuine application after installation. However, buried deep within the Trojan installer's code is a small, extensively obfuscated, and encrypted PowerShell script which runs in the background. 

Jupyter has masked itself as a variety of programs and installers. The malware's main file extension has been changed to.MSI, and it executes its obfuscated PowerShell script via several techniques. Jupyter is usually hosted on phony downloading websites which pose as real hosts. These websites typically offer a free PDF book. These can be accessed accidently by a victim or via a link in a spam email. 

It is often packaged with freeware software and certified with unrevoked digital certificates, making the installation appear more authentic. When the Windows installer package is loaded, it will present an installer pop-up for the targeted legitimate application, while loading data and running in the background. 

Jupyter has deployed itself in a variety of ways in the past campaign. The malware usually has two primary files: 
  • An executable and a Windows PowerShell script that contains the harmful code.
  • Some Jupyter variants have also dumped a temporary file (.TMP) into the victim’s %AppData%\Roaming\Temp\ directory, to construct the normal content of Jupyter's main malicious PowerShell script. 

PowerShell is used by the virus to conceal and execute its harmful code without ever publishing itself to disk on the victim's PC. It avoids writing to disk by loading Jupyter's DLL into memory reflectively. DLLs are usually injected into a process from a file written to a disk. 

Reflective DLL injection is a technique for injecting code into a victim process directly from memory rather than from disk. Because the fully un-obfuscated malware does not live on disk, it necessitates the creation of a persistence mechanism, such as registry keys that reload the malware when the victim machine boots up. As a result, Jupyter DLL is difficult to both identify and use. 

Jupyter's basic PowerShell may be split down into six different phases or components. Each phase aids in the achievement of a given objective, function, or capability. Though many Jupyter samples follow the same procedures, differences in Jupyter's PowerShell code exist, and certain samples have been observed to work in slightly different methods to achieve the same goals. 

One can make a modest tweak to the attacker's PowerShell script to save the assembly to disk instead of loading it into memory. This will also assist us in comprehending the operation of this version of SolarMarker. One can see the decompiled code, as well as the names of the classes and functions, are incorrect. Instead, they appear to be obfuscated. 

The SolarMarker backdoor is a.NET C2 client which uses an encrypted channel to interact with the C2 server. HTTP is used for communication, with POST requests being the most common. The data is secured with RSA encryption and symmetric encryption using the Advanced Encryption Standard (AES). Internal reconnaissance is carried out by the client, who gathers basic information about the victim's system and exfiltrates it through an existing C2 channel. The infostealer module has a structure that is quite identical to the backdoor module we discussed earlier, but it has more features.

By reading files relevant to the target browser, the SolarMarker infostealer module obtains login data, cookies, and web data (auto-fill) from web browsers. To decrypt the credentials, SolarMarker uses the API method CryptUnprotectData (DPAPI). 

The usefulness of behavior-based detectors in reducing the stay time of threats inside a network has been recognized by the security industry in recent years. 

Top Israeli Officials Duped by Bearded Barbie Hackers

 

Cybercriminals appear to be aggressively promoting the Remcos RAT that first appeared in hacking forums in 2016 and was marketed sold, and offered cracks on a variety of websites and forums. In 2017, researchers discovered Remcos being distributed via a malicious PowerPoint slideshow with a CVE-2017-0199 exploit. Remcos RAT is a piece of commercial software which may be purchased online. 

An "elaborate effort" targeting high-profile Israeli individuals working in critical defense, law enforcement, and emergency services sectors has been traced to a threat actor associated with Hamas' cyber warfare section. The Hamas-backed hacker outfit dubbed 'APT-C-23' was discovered catfishing Israeli officials in defense, law enforcement, and government institutions, resulting in the deployment of new malware. 

Before delivering spyware, the campaign uses advanced social engineering techniques like creating phony social media identities and maintaining a strong partnership with the targets. AridViper has previously targeted Palestinian law enforcement, military, or educational institutions, as well as the Israel Security Agency, with spear-phishing assaults (ISA). Researchers from Cisco Talos discovered AridViper assaults against activists involved in the Israel-Palestine conflict in February.

Malicious actors have built several phony Facebook pages utilizing forged credentials and pirated or AI-generated photographs of attractive women, and have used these profiles to approach their targets. The operators have spent months curating these profiles to make them appear legitimate, posting in Hebrew and alike organizations and prominent pages in Israel. The creators of these profiles create a network of friends who are actually people who work in Israel's police, defense forces, emergency services, or government. The opponents recommend transferring the chat to WhatsApp, ostensibly for more privacy, after building the target's trust by talking with individuals for a while. 

The Android app is actually the virus VolatileVenom.The icon is concealed on pre-Android 10 devices; with Android 10, the virus utilizes the Google Play installation icon. When the victim tries to sign into the Wink Chat, an error message appears, stating the app will be deleted. With a wide spectrum of espionage capabilities, VolatileVenom continues to function in the background. 

The malicious actors will eventually email the target a RAR file containing supposedly explicit photographs or videos as part of the catfishing attempts. This RAR file, on the other hand, contains the Barb(ie) installer malware, which installs the BarbWire backdoor. The filename of a sample of Barb(ie) detected by Cybereason is "Windows Notifications," and when it is made to run, it performs basic anti-analysis checks. If the host is deemed appropriate, the downloader links to an integrated C2 server. 

The BarbWire Backdoor is sent by the C2 server. The downloader contains a backup technique for finding a different C2. If the attackers need to modify the C2 from the one inserted, they can simply send an SMS message with the new destination. All inbound SMS messages are intercepted by the downloader. If one is provided by the intruders, it can just extract the new C2 information and install the backdoor. BarbWire steals data from PDFs, Office files, archives, picture files, movies, and photos, among other file types. It also checks for external media, such as a CD-ROM file, implying it's hunting for highly sensitive material which is carried around physically or over the internet. The stolen information is stored in a RAR archive and then sent to the attackers' C2 server. 

APT-C-23 employs several approaches which have been used in previous operations against Israeli targets, but it is constantly evolving with new tools and more intricate social engineering efforts. The lack of overlapping infrastructure distinguishes Operation Bearded Barbie from past missions, indicating the group's goal of avoiding notice. Another escalation for the threat actor is the usage of two backdoors, one for Windows and one for Android, resulting in very active espionage for the compromised targets.

Telegram Abused By Raccoon Stealer

 

As per a post released by Avast Threat Labs this week, Raccoon Stealer, which was first identified in April 2019, has added the capacity to keep and update its own genuine C2 addresses on Telegram's infrastructure. According to researchers, this provides them with a "convenient and trustworthy" command center on the network which they can alter on the fly. 

The malware, which is thought to have been built and maintained by Russian-linked cybercriminals, is primarily a credential stealer, but it is also capable of a variety of other nefarious activities. Based on commands from its C2, it can collect not just passwords but also cookies, saved logins and input data from browsers, login credentials from email services and messengers, crypto wallet files, data from browser plug-ins and extensions, and arbitrary files. 

As per the reports, Buer Loader and GCleaner were used to distribute Raccoon. Experts suspect it is also being distributed in the guise of false game cheats, patches for cracked software (including Fortnite, Valorant, and NBA2K22 hacks and mods), or other applications, based on some samples. 

Given since Raccoon Stealer is for sale, the only limit to its distribution methods is the imagination of the end-users. Some samples are spread unpacked, while others are protected by malware packers like Themida. It is worth mentioning whether certain samples were packed by the same packer five times in a row.

Within Telegram, the newest version of Raccoon Stealer talks with C2: According to the post, there are four "crucial" parameters for its C2 communication which are hardcoded in every Raccoon Stealer sample. Details are as follows:
  • MAIN KEY, which has changed four times throughout the year;
  • Telegram gate URLs with channel names; 
  • BotID, a hexadecimal string that is always sent to the C2; 
  • TELEGRAM KEY, a decryption key for the Telegram Gate C2 address. 

The malware decrypts MAIN KEY, which it uses to decrypt Telegram gates URLs and BotID, before hijacking Telegram for its C2. According to Martyanov, the stealer then utilizes the Telegram gate to connect to its real C2 via a series of inquiries to eventually allow it to save and change actual C2 addresses utilizing the Telegram infrastructure. 

The stealer can also transmit malware by downloading and executing arbitrary files in response to an instruction from C2. Raccoon Stealer spread roughly 185 files totaling 265 megabytes, including downloaders, clipboard crypto stealers, and the WhiteBlackCrypt ransomware, according to Avast Threat Labs.

Latest Cobalt Strike Vulnerability Allows Takedown of Hacker Servers

 

Cybersecurity experts have found Cobalt Strike (DoS) exploit that allows Beacon blocking C2 (Command and Control) communication deployments and new channels. Cobalt Strike is a genuine penetration testing tool built to work as an attack framework by red teams. Red team is a group of cybersecurity analysts that work as threat actors to attack their own organization's to find security vulnerabilities and exploits. But, Cobalt Strike is also used by hackers, that generally use it for post-hacking tasks after planting the beacons, which allows them unlimited remote access to hacked devices. With the help of these beacons, the threat actors can later use the compromised servers to deploy second-stage malware payloads or harvest data. 

The cybersecurity team at SentinelOne, SentinelLabs found about the DoS vulnerabilities, termed as CVE-2021-36798 and called "Hotcobalt" in the most recent versions of the Cobalt Strike server. SentinelLabs reports "when a Beacon stager runs, it gathers information about the computer it is running on (CPU architecture, keyboard layout, internal IP, etc.), encrypts that info using the public key, and sends it to the server in an HTTP GET request. Receiving tasks generally happens over HTTP GET requests and the Beacon replies with the task data over HTTP POST requests. Tasks are encrypted using an AES key sent by the Beacon in the registration request." 

The research revealed that one can plant fake beacons with a particular Cobalt Strike server installations by giving out fake tasks or screenshots with high file sizes to the server. The hacker could crash the server and exhaust available memory using the help of this process. The crashed server renders pre-installed beacons, not being able to communicate with the C2 servers, it restricts new beacons from getting installed on compromised systems. 

Besides this, it also interferes with the red team and malicious attacks which used the planted beacons. "One of the most famous features of Cobalt Strike is its Malleable C2. In short, this feature lets the attacker encode (“transform” in Cobalt’s language) all the beacon’s HTTP communications. The entire process described above is wrapped in the chosen Malleable profile’s transformation steps, which are also embedded in the stager itself," said SentinelLabs in its blog.