T1499.001 OS Exhaustion Flood

Adversaries may launch a denial of service (DoS) attack targeting an endpoint's operating system (OS). A system's OS is responsible for managing the finite resources as well as preventing the entire system from being overwhelmed by excessive demands on its capacity. These attacks do not need to exhaust the actual resources on a system; the attacks may simply exhaust the limits and available resources that an OS self-imposes.

Different ways to achieve this exist, including TCP state-exhaustion attacks such as SYN floods and ACK floods.(Citation: Arbor AnnualDoSreport Jan 2018) With SYN floods, excessive amounts of SYN packets are sent, but the 3-way TCP handshake is never completed. Because each OS has a maximum number of concurrent TCP connections that it will allow, this can quickly exhaust the ability of the system to receive new requests for TCP connections, thus preventing access to any TCP service provided by the server.(Citation: Cloudflare SynFlood)

ACK floods leverage the stateful nature of the TCP protocol. A flood of ACK packets are sent to the target. This forces the OS to search its state table for a related TCP connection that has already been established. Because the ACK packets are for connections that do not exist, the OS will have to search the entire state table to confirm that no match exists. When it is necessary to do this for a large flood of packets, the computational requirements can cause the server to become sluggish and/or unresponsive, due to the work it must do to eliminate the rogue ACK packets. This greatly reduces the resources available for providing the targeted service.(Citation: Corero SYN-ACKflood)

View in MITRE ATT&CK®

CRI Profile Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
DE.CM-01.02 Network traffic volume monitoring Mitigates T1499.001 OS Exhaustion Flood
Comments
This diagnostic statement may block Endpoint Denial of Service (DoS) attacks from occurring by adversaries that target endpoint's operating system (OS). Filtering boundary traffic can be used to block source addresses and block ports that are being targeted. It also blocks protocols being used for transport.
References
    PR.IR-01.03 Network communications integrity and availability Mitigates T1499.001 OS Exhaustion Flood
    Comments
    This diagnostic statement protects against OS Exhaustion Flood through the use of secure network configurations, architecture, implementations of zero trust architecture, and segmentation.
    References
      PR.PS-01.08 End-user device protection Mitigates T1499.001 OS Exhaustion Flood
      Comments
      This diagnostic statement protects against OS Exhaustion Flood through the use of limiting access to resources to only authorized devices, management of personal computing devices, network intrusion prevention, and the use of antimalware.
      References

        NIST 800-53 Mappings

        Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
        CA-07 Continuous Monitoring mitigates T1499.001 OS Exhaustion Flood
        CM-06 Configuration Settings mitigates T1499.001 OS Exhaustion Flood
        SI-10 Information Input Validation mitigates T1499.001 OS Exhaustion Flood
        SI-15 Information Output Filtering mitigates T1499.001 OS Exhaustion Flood
        CM-07 Least Functionality mitigates T1499.001 OS Exhaustion Flood
        SI-04 System Monitoring mitigates T1499.001 OS Exhaustion Flood
        AC-03 Access Enforcement mitigates T1499.001 OS Exhaustion Flood
        AC-04 Information Flow Enforcement mitigates T1499.001 OS Exhaustion Flood
        SC-07 Boundary Protection mitigates T1499.001 OS Exhaustion Flood

        VERIS Mappings

        Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
        action.hacking.variety.DoS Denial of service related-to T1499.001 OS Exhaustion Flood
        action.malware.variety.DoS DoS attack related-to T1499.001 OS Exhaustion Flood
        attribute.availability.variety.Degradation Performance degradation related-to T1499.001 OS Exhaustion Flood
        attribute.availability.variety.Loss Loss related-to T1499.001 OS Exhaustion Flood

        Azure Mappings

        Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
        ai_security_recommendations Microsoft Defender for Cloud: AI Security Recommendations technique_scores T1499.001 OS Exhaustion Flood
        Comments
        This control's "Container CPU and memory limits should be enforced" recommendation can lead to preventing resource exhaustion attacks by recommending enforcing limits for containers to ensure the runtime prevents the container from using more than the configured resource limit. Because this is a recommendation, its score is capped at Partial.
        References
        azure_ddos_protection Azure DDoS Protection technique_scores T1499.001 OS Exhaustion Flood
        Comments
        This control can protect against endpoint denial of service attacks.
        References
        azure_network_security_groups Azure Network Security Groups technique_scores T1499.001 OS Exhaustion Flood
        Comments
        This control can be used to restrict access to endpoints and thereby mitigate low-end DOS attacks.
        References
        azure_network_watcher_traffic_analytics Azure Network Watcher: Traffic Analytics technique_scores T1499.001 OS Exhaustion Flood
        Comments
        This control can detect endpoint denial of service attacks.
        References
        azure_private_link Azure Private Link technique_scores T1499.001 OS Exhaustion Flood
        Comments
        This control can protect against endpoint denial of service attacks.
        References

        AWS Mappings

        Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
        amazon_virtual_private_cloud Amazon Virtual Private Cloud technique_scores T1499.001 OS Exhaustion Flood
        Comments
        VPC security groups and network access control lists (NACLs) can be used to restrict access to endpoints but will prove effective at mitigating only low-end DOS attacks resulting in a Minimal score.
        References
          aws_config AWS Config technique_scores T1499.001 OS Exhaustion Flood
          Comments
          The "elb-cross-zone-load-balancing-enabled" managed rule can verify that load balancing is properly configured, which can mitigate adversaries' ability to perform Denial of Service (DoS) attacks and impact resource availability. "cloudfront-origin-failover-enabled" can verify that failover policies are in place to increase CloudFront content availability. Coverage factor is minimal for these rules, since they are specific to a subset of the available AWS services, resulting in an overall score of Minimal.
          References
            aws_network_firewall AWS Network Firewall technique_scores T1499.001 OS Exhaustion Flood
            Comments
            AWS Network Firewall has the ability to pass, drop, or alert on traffic based on the network protocol as well as perform deep packet inspection on the payload. This functionality can be used to block adversaries from carrying out denial of service attacks by implementing restrictions on which IP addresses and domains can access the resources (e.g., allow lists) as well as which protocol traffic is permitted. That is, the AWS Network Firewall could block the source of the denial of service attack. This mapping is given a score of Partial because the source of the attack would have to be known before rules could be put in place to protect against it.
            References
              aws_shield AWS Shield technique_scores T1499.001 OS Exhaustion Flood
              Comments
              AWS Shield Standard provides protection and response to these Denial of Service attacks in real time by using a network traffic baseline and identifying anomalies among other techniques.
              References