Service Exhaustion Flood
Service Exhaustion Flood [T1499.002]
Last updated
Service Exhaustion Flood [T1499.002]
Last updated
Name: Service Exhaustion Flood
ID: T1499.002
Tactics:
Technique:
Service Exhaustion Flood (T1499.002) is a sub-technique within the MITRE ATT&CK framework, categorized under the broader Impact tactic (T1499). This sub-technique specifically involves overwhelming targeted services or resources with excessive traffic or requests, exhausting their available resources and causing denial of legitimate service requests. Attackers utilize this technique to disrupt availability, degrade performance, or completely incapacitate targeted systems and services, leading to denial-of-service (DoS) conditions.
Service Exhaustion Flood attacks primarily aim to consume finite system resources, such as CPU cycles, memory, bandwidth, or connection pools, by flooding the targeted service with a high volume of traffic or requests. The key objective is to exhaust these resources, thereby preventing legitimate users from accessing the service.
Common methods and mechanisms employed in Service Exhaustion Flood attacks include:
TCP SYN Floods:
Attackers initiate numerous TCP connection requests (SYN packets) without completing the TCP handshake.
The targeted server allocates resources for these half-open connections, eventually exhausting its connection pool.
Legitimate connection requests are subsequently denied or ignored.
UDP Floods:
Attackers send large volumes of UDP packets to random ports on the targeted system.
The targeted system expends resources processing and responding to these packets, leading to exhaustion of bandwidth or processing power.
HTTP GET/POST Floods:
Attackers generate excessive HTTP requests to web servers, consuming server resources such as CPU, memory, database connections, or bandwidth.
Automated tools or botnets can rapidly generate large request volumes, overwhelming the targeted web application or server.
ICMP Floods:
Attackers send a high volume of ICMP echo requests (ping) to exhaust bandwidth or processing resources.
The target system becomes unresponsive or severely degraded.
Attackers often leverage botnets, compromised devices, or cloud-based resources to amplify the scale and intensity of these attacks. Additionally, attackers may spoof IP addresses or employ distributed attack methods (DDoS) to complicate attribution and mitigation efforts.
Service Exhaustion Flood attacks typically appear in various attack scenarios and stages, including:
Extortion campaigns:
Attackers threaten businesses with sustained DoS attacks unless ransom payments are made.
Attackers may demonstrate capability through short-duration floods before demanding payment.
Hacktivism:
Politically or ideologically motivated attackers disrupt targeted services to make a statement or gain media attention.
Competitive sabotage:
Malicious actors disrupt competitors' online presence or services to gain market advantage.
Distraction attacks:
Attackers launch floods to divert attention and resources away from other malicious activities, such as data exfiltration or unauthorized access attempts.
State-sponsored cyber operations:
Nation-state actors disrupt critical infrastructure, government, or military services as part of cyber warfare or espionage activities.
Gaming industry targeting:
Attackers disrupt online gaming services or platforms for competitive advantage or to impact user experience negatively.
Effective detection of Service Exhaustion Flood attacks relies on robust monitoring, alerting, and analysis capabilities. Common detection methods, tools, and indicators of compromise (IoCs) include:
Network Monitoring and Anomaly Detection:
Tools such as network intrusion detection systems (IDS) or network behavior anomaly detection (NBAD) systems identify abnormal traffic spikes or deviations from baseline network activity.
Sudden increases in traffic volume, unusual traffic patterns, or bursts of connection attempts indicate potential flooding attacks.
Traffic Analysis and Flow Monitoring:
NetFlow, sFlow, or IPFIX analysis helps identify excessive traffic from specific IP addresses, subnets, or geographical regions.
Identification of traffic anomalies, such as disproportionate SYN packets, UDP packets, or ICMP echo requests, can signal flooding attempts.
Web Application Firewalls (WAF):
WAFs detect and block abnormal HTTP request patterns, such as high-frequency GET or POST requests from single or distributed sources.
Identification of unusual user-agent strings, request headers, or repeated requests to resource-intensive endpoints.
System Resource Monitoring:
Monitoring server resources (CPU, memory, connection pools) for sudden spikes or saturation events indicates resource exhaustion attacks.
Tools like Nagios, Zabbix, Splunk, or Prometheus enable real-time monitoring and alerting for resource exhaustion conditions.
Specific Indicators of Compromise (IoCs):
Sudden spikes in SYN packets without corresponding ACK packets.
Unusual volumes of UDP packets directed to random or closed ports.
High-frequency HTTP requests with repetitive patterns or abnormal headers.
Unusual ICMP echo request volume from external IP addresses.
Early detection and mitigation of Service Exhaustion Flood attacks are critically important due to their significant potential impacts on systems and networks, including:
Service disruption and downtime:
Flooding attacks cause targeted services to become unavailable, directly impacting business operations, revenue streams, and user experience.
Operational disruption and productivity loss:
Organizations experience reduced productivity and increased operational overhead as they attempt to mitigate and recover from attacks.
Reputational damage:
Service outages or degraded performance negatively impact customer perception, trust, and brand reputation, potentially resulting in long-term customer attrition.
Financial losses:
Downtime, remediation efforts, lost sales opportunities, and potential compliance fines result in substantial financial implications.
Secondary attack enablement:
Flooding attacks may serve as distractions, enabling attackers to conduct additional malicious activities such as data breaches, unauthorized access, or lateral movement.
Impact on critical infrastructure:
Attacks targeting critical infrastructure, healthcare services, or emergency systems pose risks to public safety and national security.
Early detection enables organizations to implement rapid mitigation measures, maintain service availability, reduce operational disruption, and minimize potential financial and reputational damage.
Real-world examples of Service Exhaustion Flood attacks include:
Mirai Botnet (2016):
Attackers leveraged the Mirai botnet, comprising compromised IoT devices, to launch massive DDoS attacks against DNS provider Dyn.
Attack involved UDP floods and TCP SYN floods, causing widespread disruption of major internet services, including Twitter, Netflix, and Amazon.
Operation Ababil (2012-2013):
Attackers conducted sustained HTTP GET and POST floods against major U.S. financial institutions, including Bank of America, JPMorgan Chase, and Wells Fargo.
Attackers utilized botnets and sophisticated request patterns to overwhelm web servers, causing prolonged outages and significant financial impact.
GitHub Attack (2018):
Attackers executed a massive amplification attack using Memcached servers, directing high-volume UDP traffic toward GitHub infrastructure.
The attack peaked at 1.35 Tbps, temporarily disrupting GitHub services until mitigated by DDoS protection measures.
Estonian Cyber Attacks (2007):
Coordinated ICMP, TCP SYN, and UDP floods targeted Estonian government, media, and financial websites.
Attackers overwhelmed network resources, causing nationwide disruption and highlighting cyber warfare risks.
PlayStation Network Attack (2014):
Attackers launched TCP SYN floods and UDP floods against Sony's PlayStation Network, causing multi-day service disruptions.
Users experienced severe connectivity issues, impacting millions of gamers worldwide.
These examples demonstrate the diverse methods, tools, and impacts associated with Service Exhaustion Flood attacks, underscoring the importance of proactive detection and mitigation strategies.