EXPLORE DETECTIONS
Detect Spike in AWS Security Hub Alerts for EC2 Instance
The following analytic identifies a spike in the number of AWS Security Hub alerts for an EC2 instance within a 4-hour interval. It leverages AWS Security Hub findings data, calculating the average and standard deviation of alerts to detect anomalies. This activity is significant for a SOC as a sudden increase in alerts may indicate potential security incidents or misconfigurations requiring immediate attention. If confirmed malicious, this could signify an ongoing attack, leading to unauthorized access, data exfiltration, or disruption of services on the affected EC2 instance.
Detect Spike in AWS Security Hub Alerts for User
The following analytic identifies a spike in the number of AWS Security Hub alerts for an AWS IAM User within a 4-hour interval. It leverages AWS Security Hub findings data, calculating the average and standard deviation of alerts to detect significant deviations. This activity is significant as a sudden increase in alerts for a specific user may indicate suspicious behavior or a potential security incident. If confirmed malicious, this could signify an ongoing attack, unauthorized access, or misuse of IAM credentials, potentially leading to data breaches or further exploitation.
Detect Spike in blocked Outbound Traffic from your AWS
The following analytic identifies spikes in blocked outbound network connections originating from within your AWS environment. It leverages VPC Flow Logs data from CloudWatch, focusing on blocked actions from internal IP ranges to external destinations. This detection is significant as it can indicate potential exfiltration attempts or misconfigurations leading to data leakage. If confirmed malicious, such activity could allow attackers to bypass network defenses, leading to unauthorized data transfer or communication with malicious external entities.
Detect Spike in S3 Bucket deletion
The following analytic identifies a spike in API activity related to the deletion of S3 buckets in your AWS environment. It leverages AWS CloudTrail logs to detect anomalies by comparing current deletion activity against a historical baseline. This activity is significant as unusual spikes in S3 bucket deletions could indicate malicious actions such as data exfiltration or unauthorized data destruction. If confirmed malicious, this could lead to significant data loss, disruption of services, and potential exposure of sensitive information. Immediate investigation is required to determine the legitimacy of the activity.
Detect Traffic Mirroring
The following analytic detects the initiation of traffic mirroring sessions on Cisco network devices. It leverages logs with specific mnemonics and facilities related to traffic mirroring, such as "ETH_SPAN_SESSION_UP" and "PKTCAP_START." This activity is significant because adversaries may use traffic mirroring to exfiltrate data by duplicating and forwarding network traffic to an external destination. If confirmed malicious, this could allow attackers to capture sensitive information, monitor network communications, and potentially compromise the integrity and confidentiality of the network.
Detect Unauthorized Assets by MAC address
The following analytic identifies unauthorized devices attempting to connect to the organization's network by inspecting DHCP request packets. It detects this activity by comparing the MAC addresses in DHCP requests against a list of known authorized devices stored in the assets_by_str.csv file. This activity is significant for a SOC because unauthorized devices can pose security risks, including potential data breaches or network disruptions. If confirmed malicious, this activity could allow an attacker to gain unauthorized network access, potentially leading to further exploitation or data exfiltration.
Detect Use of cmd exe to Launch Script Interpreters
The following detects the execution of cscript.exe or wscript.exe processes spawned by cmd.exe, leveraging Endpoint Detection and Response (EDR) telemetry mapped to the Endpoint data model, with additional contextual filtering to improve fidelity and reduce false positives. It focuses on executions originating from user-writable directories such as Users, AppData, Temp, and Downloads, which are commonly abused by attackers to stage and execute malicious scripts, while excluding trusted system paths like C:\Windows\System32\ and C:\Program Files\ that are typically associated with legitimate activity. The detection also filters out service accounts (e.g., accounts ending with $ or known naming conventions) to minimize noise from automated processes and incorporates command-line context to better assess script execution patterns and identify potentially suspicious behavior.
Detect Web Access to Decommissioned S3 Bucket
This detection identifies web requests to domains that match previously decommissioned S3 buckets through web proxy logs. This activity is significant because attackers may attempt to access or recreate deleted S3 buckets that were previously public to hijack them for malicious purposes. If successful, this could allow attackers to host malicious content or exfiltrate data through compromised bucket names that may still be referenced by legitimate applications.
Detect Windows DNS SIGRed via Splunk Stream
The following analytic detects attempts to exploit the SIGRed vulnerability (CVE-2020-1350) in Windows DNS servers. It leverages Splunk Stream DNS and TCP data to identify DNS SIG and KEY records, as well as TCP payloads exceeding 65KB. This activity is significant because SIGRed is a critical wormable vulnerability that allows remote code execution. If confirmed malicious, an attacker could gain unauthorized access, execute arbitrary code, and potentially disrupt services, leading to severe data breaches and infrastructure compromise. Immediate investigation and remediation are crucial to mitigate these risks.
Detect Windows DNS SIGRed via Zeek
The following analytic detects the presence of SIGRed, a critical DNS vulnerability, using Zeek DNS and Zeek Conn data. It identifies specific DNS query types (SIG and KEY) and checks for high data transfer within a flow. This detection is significant because SIGRed allows attackers to execute remote code on Windows DNS servers, potentially leading to unauthorized access and control. If confirmed malicious, this activity could result in data exfiltration, service disruption, or further network compromise. Immediate investigation and mitigation, such as patching or isolating the affected server, are crucial.
Detect WMI Event Subscription Persistence
The following analytic identifies the creation of WMI Event Subscriptions, which can be used to establish persistence or perform privilege escalation. It detects EventID 19 (EventFilter creation), EventID 20 (EventConsumer creation), and EventID 21 (FilterToConsumerBinding creation) from Sysmon logs. This activity is significant because WMI Event Subscriptions can execute code with elevated SYSTEM privileges, making it a powerful persistence mechanism. If confirmed malicious, an attacker could maintain long-term access, escalate privileges, and execute arbitrary code, posing a severe threat to the environment.
Detect Zerologon via Zeek
The following analytic detects attempts to exploit the Zerologon CVE-2020-1472 vulnerability via Zeek RPC. It leverages Zeek DCE-RPC data to identify specific operations: NetrServerPasswordSet2, NetrServerReqChallenge, and NetrServerAuthenticate3. This activity is significant because it indicates an attempt to gain unauthorized access to a domain controller, potentially leading to a complete takeover of an organization's IT infrastructure. If confirmed malicious, the impact could be severe, including data theft, ransomware deployment, or other devastating outcomes. Immediate investigation of the identified IP addresses and RPC operations is crucial.
Detection of tools built by NirSoft
The following analytic identifies the execution of tools built by NirSoft by detecting specific command-line arguments such as "/stext" and "/scomma". It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line executions. This activity is significant because NirSoft tools, while legitimate, can be exploited by attackers for malicious purposes such as credential theft or system reconnaissance. If confirmed malicious, this activity could lead to unauthorized access, data exfiltration, or further compromise of the affected system.
Disable AMSI Through Registry
The following analytic detects modifications to the Windows registry that disable the Antimalware Scan Interface (AMSI) by setting the "AmsiEnable" value to "0x00000000". This detection leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path "*\\SOFTWARE\\Microsoft\\Windows Script\\Settings\\AmsiEnable". Disabling AMSI is significant as it is a common technique used by ransomware, Remote Access Trojans (RATs), and Advanced Persistent Threats (APTs) to evade detection and impair defenses. If confirmed malicious, this activity could allow attackers to execute payloads with minimal alerts, leading to potential system compromise and data exfiltration.
Disable Defender AntiVirus Registry
The following analytic detects the modification of Windows Defender registry settings to disable antivirus and antispyware protections. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths associated with Windows Defender policies. This activity is significant because disabling antivirus protections is a common tactic used by adversaries to evade detection and maintain persistence on compromised systems. If confirmed malicious, this action could allow attackers to execute further malicious activities undetected, leading to potential data breaches, system compromise, and further propagation of malware within the network.
Disable Defender BlockAtFirstSeen Feature
The following analytic detects the modification of the Windows registry to disable the Windows Defender BlockAtFirstSeen feature. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path associated with Windows Defender SpyNet and the DisableBlockAtFirstSeen value. This activity is significant because disabling this feature can allow malicious files to bypass initial detection by Windows Defender, increasing the risk of malware infection. If confirmed malicious, this action could enable attackers to execute malicious code undetected, leading to potential system compromise and data breaches.
Disable Defender Enhanced Notification
The following analytic detects the modification of the registry to disable Windows Defender's Enhanced Notification feature. It leverages data from Endpoint Detection and Response (EDR) agents, specifically monitoring changes to the registry path associated with Windows Defender reporting. This activity is significant because disabling Enhanced Notifications can prevent users and administrators from receiving critical security alerts, potentially allowing malicious activities to go unnoticed. If confirmed malicious, this action could enable an attacker to bypass detection mechanisms, maintain persistence, and escalate their activities without triggering alerts.
Disable Defender MpEngine Registry
The following analytic detects the modification of the Windows Defender MpEngine registry value, specifically setting MpEnablePus to 0x00000000. This detection leverages endpoint registry logs, focusing on changes within the path "*\\Policies\\Microsoft\\Windows Defender\\MpEngine*". This activity is significant as it indicates an attempt to disable key Windows Defender features, potentially allowing malware to evade detection. If confirmed malicious, this could lead to undetected malware execution, persistence, and further system compromise. Immediate investigation and endpoint isolation are recommended.
Disable Defender Spynet Reporting
The following analytic detects the modification of the registry to disable Windows Defender SpyNet reporting. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path associated with Windows Defender SpyNet settings. This activity is significant because disabling SpyNet reporting can prevent Windows Defender from sending telemetry data, potentially allowing malicious activities to go undetected. If confirmed malicious, this action could enable an attacker to evade detection, maintain persistence, and carry out further attacks without being flagged by Windows Defender.
Disable Defender Submit Samples Consent Feature
The following analytic detects the modification of the Windows registry to disable the Windows Defender Submit Samples Consent feature. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path associated with Windows Defender SpyNet and the SubmitSamplesConsent value set to 0x00000000. This activity is significant as it indicates an attempt to bypass or evade detection by preventing Windows Defender from submitting samples for further analysis. If confirmed malicious, this could allow an attacker to execute malicious code without being detected by Windows Defender, leading to potential system compromise.
Disable ETW Through Registry
The following analytic detects modifications to the registry that disable the Event Tracing for Windows (ETW) feature. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path "*\\SOFTWARE\\Microsoft\\.NETFramework\\ETWEnabled" with a value set to "0x00000000". This activity is significant because disabling ETW can allow attackers to evade detection mechanisms, making it harder for security tools to monitor malicious activities. If confirmed malicious, this could enable attackers to execute payloads with minimal alerts, impairing defenses and potentially leading to further compromise of the system.
Disable Logs Using WevtUtil
The following analytic detects the execution of "wevtutil.exe" with parameters to disable event logs. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because disabling event logs is a common tactic used by ransomware to evade detection and hinder forensic investigations. If confirmed malicious, this action could allow attackers to operate undetected, making it difficult to trace their activities and respond effectively to the incident.
Disable Registry Tool
The following analytic detects modifications to the Windows registry aimed at disabling the Registry Editor (regedit). It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\DisableRegistryTools" with a value of "0x00000001". This activity is significant because malware, such as RATs or trojans, often disable registry tools to prevent the removal of their entries, aiding in persistence and defense evasion. If confirmed malicious, this could hinder incident response efforts and allow the attacker to maintain control over the compromised system.
Disable Schedule Task
The following analytic detects the execution of a command to disable an existing scheduled task using 'schtasks.exe' with the '/change' and '/disable' parameters. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. Disabling scheduled tasks is significant as it is a common tactic used by adversaries, including malware like IcedID, to disable security applications and evade detection. If confirmed malicious, this activity could allow attackers to persist undetected, disable critical security defenses, and further compromise the targeted host.