Detections

Explore public detection logic contributed by the community across SIEM and rule languages.

18 detections

This rule monitors for two types of anomalous network behavior: first, it identifies connections to known domains from IP addresses not previously associated with those domains over a seven-day lookback period. Second, it identifies HTTP proxy responses (from Zscaler or Squid) where the content-length significantly deviates from the historical baseline for specific URLs. These patterns are potential indicators of C2 channel shifts or data exfiltration via web protocols.
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Ankit Mehta@Secvyn
Bharat Cyber Guardians
4 months ago
109
This rule monitors for two types of anomalous network behavior: first, it identifies connections to known domains from IP addresses not previously associated with those domains over a seven-day lookback period. Second, it identifies HTTP proxy responses (from Zscaler or Squid) where the content-length significantly deviates from the historical baseline for specific URLs. These patterns are potential indicators of C2 channel shifts or data exfiltration via web protocols.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
005
This rule detects large data uploads over HTTPS (port 443) from the home network to any external destination. Specifically, it triggers if the data size in a single TCP flow to the server exceeds 65,000 bytes. To prevent excessive alerts, it uses a threshold of 20 such events within 60 seconds, tracked by the source IP address. This behavior is indicative of potential data exfiltration.
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Darshan Thummar@Mighty
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Detections.ai Community
5 months ago
004
KQL Query from file: Ottercookie Detection
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
3171
KQL Query
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
4043
Well-known DNS Exfiltration tools execution
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
0015
Well-known DNS Exfiltration tools execution
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
0012
Snip3 is a family of related remote access trojans. Although the malware in this family contain numerous small variations, they all exhibit similar behaviors and techniques.
The following query looks for network connections using any protocols associated with recent RevengeRAT, AsyncRAT, and other malware campaigns targeting the aviation industry.
This activity is often followed by connections to copy-and-paste sites such as pastebin.com, stikked.ch, academia.edu, and archive.org. Many of these connections will occur on non-standard ports.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1029
'This composite hunting query will highlight any HTTP traffic in CommonSecurityLog web proxies (such as ZScaler) that match known patterns used by red teaming tools potentially stolen from FireEye. Most FireEye red teaming tools are designed to mimic
legitimate API activity, false positives are common. This query includes a basic check to determine how common a hostname is in you environment, and allows you to modify this threshold to remove legitimate traffic from the query results.
This query contains only a subset of potential FireEye red team tool communications, and therefore should not be relied upon alone :) .'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0027
LemonDuck is an actively updated and robust malware primarily known for its botnet and cryptocurrency mining objectives. First discovered in 2019, LemonDuck has since adopted more sophisticated behavior and escalated its operations in 2021. Today, beyond using resources for its traditional bot and mining activities, LemonDuck steals credentials, removes security controls, spreads via emails, moves laterally, and ultimately drops more tools for human-operated activity.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0021
This is a query to retrieve last 30 days network connections to known Dofoil NameCoin servers.
The full article is available here: https://cloudblogs.microsoft.com/microsoftsecure/2018/04/04/hunting-down-dofoil-with-windows-defender-atp.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1015
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0011
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0010
This rule detects the execution of well-known DNS exfiltration and tunneling tools, specifically 'iodine.exe' and 'dnscat2'. These tools are commonly used by adversaries to establish covert communication channels over DNS, allowing for data exfiltration and command and control activities that might bypass traditional network defenses.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0046
Detects the execution of 'openssl' with specific command-line arguments to connect to an IP address on ports 443 or 8080. This activity has been observed in campaigns by UNC4841 for SSL certificate exfiltration and as a C2 channel using named pipes. Further investigation of commands executed in the temporal vicinity of this activity is recommended.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1029
Well-known DNS Exfiltration tools execution
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
000