Compute Hijacking (T1496.001)
SMS Pumping [T1496.001]
Last updated
SMS Pumping [T1496.001]
Last updated
Name: Compute Hijacking
ID: T1496.001
Tactics:
Technique:
SMS Pumping (T1496.001) is a sub-technique within the MITRE ATT&CK framework categorized under Resource Hijacking (T1496). It involves adversaries exploiting compromised or malicious mobile applications and services to send large volumes of SMS messages, often to premium-rate numbers, resulting in financial gain for attackers and financial loss for victims. This technique leverages unauthorized use of user resources and can also be employed for denial-of-service (DoS) attacks by overwhelming SMS gateways and mobile networks.
SMS Pumping typically operates through malicious or compromised mobile applications installed on victim devices. Attackers embed hidden code or functionalities within seemingly legitimate apps, which then silently send SMS messages without user consent or knowledge. Technical mechanisms include:
Malicious Mobile Applications:
Adversaries embed malicious code within mobile apps distributed via third-party app stores or compromised official app stores.
The malicious code runs silently in the background, automatically sending SMS messages to premium-rate or attacker-controlled numbers.
Trojanized Applications:
Legitimate apps are modified (trojanized) to include hidden SMS sending functionalities.
Users unknowingly install these modified apps, believing them to be authentic and safe.
Automated SMS Sending:
Malicious code leverages device APIs to programmatically send SMS messages.
Messages are typically sent to premium-rate numbers, generating revenue for the attacker at the victim's expense.
Command and Control (C2):
Attackers may remotely control compromised devices via C2 servers, instructing them when and how frequently to send SMS messages.
Communication with C2 servers can be encrypted or obfuscated to evade detection.
Financial Fraud and Revenue Generation:
Attackers register premium-rate SMS numbers or partner with fraudulent SMS service providers.
Each SMS message sent generates revenue, charged directly to the victim's mobile bill.
Denial-of-Service (DoS):
Large-scale SMS pumping can overwhelm mobile network operators or targeted SMS gateways, causing disruptions in legitimate SMS traffic.
Attackers employ SMS Pumping in various attack scenarios and stages, including:
Financial Fraud Attacks:
Attackers aim to directly monetize compromised mobile devices by sending SMS messages to premium-rate numbers.
Victims incur unexpected charges, benefiting adversaries financially.
Massive Spam Campaigns:
SMS pumping is used to distribute spam, phishing messages, or malicious links on a large scale.
Attackers leverage compromised devices for mass propagation of malicious content.
Mobile Malware Campaigns:
SMS Pumping is frequently integrated into mobile malware as a monetization strategy.
Attackers embed SMS sending functionalities within mobile Trojans, ransomware, or spyware.
Denial-of-Service (DoS) Attacks:
Attackers intentionally overload targeted SMS gateways or mobile networks by sending massive volumes of SMS messages.
Can disrupt critical communication channels, causing operational and reputational damage.
Initial Access and Persistence:
SMS Pumping can be used as a secondary monetization method after gaining initial access to mobile devices.
Persistent malicious applications continuously send SMS messages, generating sustained revenue for attackers.
Detection of SMS Pumping involves various methods, tools, and indicators of compromise (IoCs):
Monitoring SMS Traffic:
Analyze SMS logs and message sending patterns for unusual volume spikes or frequent messaging to premium-rate numbers.
Mobile Device Management (MDM) solutions can provide visibility into SMS activities.
Behavioral Analysis and Anomaly Detection:
Implement anomaly detection tools to identify abnormal SMS sending behavior, such as frequent SMS sending at odd hours or from unusual locations.
Machine learning-based tools can detect deviations from normal user behavior patterns.
Mobile Endpoint Protection Solutions:
Deploy mobile antivirus or endpoint detection and response (EDR) tools to identify malicious mobile applications.
Regularly scan devices for known malicious apps or suspicious app behaviors.
Application Analysis and Sandboxing:
Analyze mobile applications in sandbox environments before deployment or installation.
Identify hidden functionalities or unauthorized SMS sending capabilities within applications.
Network Monitoring and Intrusion Detection Systems (IDS):
Monitor network traffic from mobile devices for communication with known malicious C2 servers.
Detect unusual outbound connections indicative of compromised devices.
Indicators of Compromise (IoCs):
Presence of unauthorized or unfamiliar applications on mobile devices.
Frequent SMS messages sent to premium-rate or international numbers.
Unexpected charges on mobile bills related to premium SMS services.
Communication with known malicious domains or IP addresses associated with SMS Pumping campaigns.
Early detection of SMS Pumping is critical due to its significant potential impacts:
Financial Impact:
Victims incur substantial monetary losses from unauthorized premium-rate SMS charges.
Organizations may face increased operational costs and financial liabilities.
Operational Disruption:
High-volume SMS pumping can overwhelm SMS gateways and mobile network infrastructure.
Legitimate SMS communications can be disrupted, affecting business operations and customer interactions.
Reputational Damage:
Organizations associated with compromised apps or services may experience severe reputational harm.
Customer trust can be eroded, leading to loss of business and brand damage.
Privacy and Compliance Risks:
Unauthorized SMS sending violates user privacy and data protection regulations.
Organizations may face regulatory fines, legal actions, and compliance audits.
Indicator of Broader Compromise:
SMS Pumping often indicates that devices are compromised, potentially exposing sensitive data or enabling further malicious activities.
Early detection can help prevent additional security incidents, data breaches, or lateral movement by attackers.
Real-world examples of SMS Pumping incidents include:
ExpensiveWall Malware Campaign:
Malicious Android apps, such as wallpaper apps, infected millions of devices globally.
Apps silently sent SMS messages to premium-rate numbers, generating revenue for attackers.
Impact: Millions of users incurred unexpected charges; widespread financial losses.
Joker Malware:
Android malware distributed via compromised apps on official Google Play Store.
Malware subscribed victims to premium SMS services without their knowledge.
Impact: Significant financial losses for users; millions of downloads before detection and removal.
RuFraud Campaign:
Large-scale SMS pumping campaign targeting Android users via fraudulent apps.
Apps automatically sent SMS messages to premium numbers, primarily targeting users in Eastern Europe and Russia.
Impact: Victims faced substantial unauthorized charges; attackers profited significantly.
FakePlayer Trojan:
Early Android malware posing as a media player application.
Automatically sent SMS messages to premium-rate numbers upon installation.
Impact: Users incurred financial losses; highlighted emerging threats in mobile security.
Gazon Malware:
Malware propagated via SMS phishing messages containing malicious links to compromised apps.
Upon installation, apps sent SMS messages to premium-rate numbers.
Impact: Extensive financial damage to victims; rapid propagation through SMS spam.
These examples illustrate the widespread nature of SMS Pumping attacks, the variety of malicious apps and techniques used, and the significant financial and operational impacts on victims and organizations.