Detections

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

268 detections

Detects potentially highly relevant antivirus events in the application log based on known virus signature names and malware keywords.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
16 days ago
102
The following analytic identifies security events from Microsoft Defender, focusing on Exploit Guard and Attack Surface Reduction (ASR) features. It detects Event IDs 1121, 1126, 1131, and 1133 for blocked operations, and Event IDs 1122, 1125, 1132, and 1134 for audit logs. Event ID 1129 indicates user overrides, while Event ID 5007 signals configuration changes. This detection uses a lookup to correlate ASR rule GUIDs with descriptive names. Monitoring these events is crucial for identifying unauthorized operations, potential security breaches, and policy enforcement issues. If confirmed malicious, attackers could bypass security measures, execute unauthorized actions, or alter system configurations.
Splunk Security@SplunkSecurity
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Splunk Security Content
23 days ago
003
This detection searches for ASR audit events that are generated when a process or application attempts to perform an action that would be blocked by an ASR rule, but is allowed to proceed for auditing purposes.
Splunk Security@SplunkSecurity
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Splunk Security Content
23 days ago
002
This detection searches for ASR block events that are generated when a process or application attempts to perform an action that is blocked by an ASR rule.
Typically, these will be enabled in block most after auditing and tuning the ASR rules themselves.
Splunk Security@SplunkSecurity
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Splunk Security Content
23 days ago
001
Detects a sequence of events indicative of Bring Your Own Vulnerable Driver (BYOVD) exploitation. The rule correlates the creation of a new service with kernel-mode drivers, the loading of a signed driver, and the subsequent termination or disabling of common EDR security processes within a short timeframe, suggesting the exploitation of the driver to bypass EDR defenses.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
2010
Detects attempts to terminate common antivirus and security software processes using 'taskkill.exe' with force flags. The rule specifically correlates this behavior with SQL Server processes (initiating or present on the host), suggesting an attempt to disable security controls to facilitate unauthorized activity or persistence.
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Ibrahim Saud@tektrix
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Detections.ai Community
29 days ago
005
Detects attempts to disable or tamper with Microsoft Windows Defender via registry modifications or malicious PowerShell/reg.exe commands, specifically targeting security settings like DisableAntiSpyware, DisableRealtimeMonitoring, and exclusion paths.
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Ankit Mehta@Secvyn
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SlimKQL 2026
1 month ago
9012
Detects evidence of potential adversarial interference with Windows Defender updates and MRT.exe (Malicious Software Removal Tool). The rule correlates high volumes of temporary file creation in user directories with unauthorized access to MRT.exe by third-party processes and repeated Windows Defender update failures, indicating a potential attempt to disrupt endpoint security operations.
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Ankit Mehta@Secvyn
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SlimKQL
1 month ago
16137
Detects a behavioral pattern characteristic of Everest ransomware, where a sequence of rapid process terminations occurs within a 20-second window. The rule identifies the coordinated termination of security/analysis tools, antivirus/backup/database services, and other high-memory processes on a single device, excluding known legitimate maintenance processes.
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Arnold Chan@slaz
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Detections.ai Community
28 days ago
003
Detects attempts to disable, modify, or stop security software and endpoint protection services. The rule monitors for registry changes to Windows Defender settings, manual service management commands (sc, net) targeting security processes, and PowerShell execution using 'Set-MpPreference' to disable protection features.
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Ibrahim Saud@tektrix
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Detections.ai Community
27 days ago
102
Detects evidence of potential adversarial interference with Windows Defender updates and MRT.exe (Malicious Software Removal Tool). The rule correlates high volumes of temporary file creation in user directories with unauthorized access to MRT.exe by third-party processes and repeated Windows Defender update failures, indicating a potential attempt to disrupt endpoint security operations.
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Ankit Mehta@Secvyn
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Detection & Hunting Community
1 month ago
11024
Detects multiple methods of tampering with Windows Defender security controls within a short time window. This includes PowerShell commands to modify Defender preferences (e.g., disabling Real-time Monitoring or adding exclusions), modifications to Defender-related registry keys, and attempts to stop or disable the WinDefend service.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
106
Detects a behavioral pattern characteristic of Everest ransomware, where a sequence of rapid process terminations occurs within a 20-second window. The rule identifies the coordinated termination of security/analysis tools, antivirus/backup/database services, and other high-memory processes on a single device, excluding known legitimate maintenance processes.
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Arnold Chan@slaz
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Hunters
28 days ago
001
Detects a behavioral pattern characteristic of Everest ransomware, where a sequence of rapid process terminations occurs within a 20-second window. The rule identifies the coordinated termination of security/analysis tools, antivirus/backup/database services, and other high-memory processes on a single device, excluding known legitimate maintenance processes.
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Arnold Chan@slaz
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Midnight Slayer
28 days ago
001
Detects a behavioral pattern characteristic of Everest ransomware, where a sequence of rapid process terminations occurs within a 20-second window. The rule identifies the coordinated termination of security/analysis tools, antivirus/backup/database services, and other high-memory processes on a single device, excluding known legitimate maintenance processes.
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Arnold Chan@slaz
Defender - KQL
28 days ago
001
Detects the use of PowerShell to modify Microsoft Defender antivirus preferences by adding exclusion paths or processes. This behavior is indicative of an attacker attempting to bypass security software detection by excluding their malicious tools or staging areas from scanning.
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Ankit Mehta@Secvyn
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Detections.ai Community
1 month ago
104
The following analytic detects creation and removal of intermediary remediation artifacts of Windows Defender, during exploitation of ShieldCrash attacks.
Exploit abuses the race condition between file validation and its remediation performed by Windows Defender. In between these steps, ShieldCrash changes the
symbolic link to redirect the remediation process to a staging directory controlled by the attacker. This detection aims to detect creation of defender artifact,
its alternate data stream, and their subsequent removal.
Splunk Security@SplunkSecurity
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Splunk Security Content
26 days ago
000
Detects evidence of potential adversarial interference with Windows Defender updates and MRT.exe (Malicious Software Removal Tool). The rule correlates high volumes of temporary file creation in user directories with unauthorized access to MRT.exe by third-party processes and repeated Windows Defender update failures, indicating a potential attempt to disrupt endpoint security operations.
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Ankit Mehta@Secvyn
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Detections.ai Community
1 month ago
708
This rule detects potential HTML smuggling activity by identifying a browser process writing an executable file named 'config.exe' to the user's Downloads folder without a traditional network download event, followed immediately by Microsoft Defender SmartScreen or Antivirus reporting a warning or scan failure on the file. This behavior is indicative of a payload being reconstructed on the client-side via JavaScript blobs or data URLs, which is a common characteristic of HTML smuggling delivery chains.
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Ankit Mehta@Secvyn
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SlimKQL
1 month ago
101
This rule detects potential HTML smuggling activity by identifying a browser process writing an executable file named 'config.exe' to the user's Downloads folder without a traditional network download event, followed immediately by Microsoft Defender SmartScreen or Antivirus reporting a warning or scan failure on the file. This behavior is indicative of a payload being reconstructed on the client-side via JavaScript blobs or data URLs, which is a common characteristic of HTML smuggling delivery chains.
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Ankit Mehta@Secvyn
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Detections.ai Community
1 month ago
001
Detects the use of PowerShell to add an exclusion to Microsoft Defender. The detection looks for common obfuscation flags (Hidden, NonI, NoP, Bypass) in the command line and targets the MicrosoftEdgeUpdateCore executable or DLL for exclusion, which is a common persistence or evasion technique. It excludes parent processes known for administrative activity to reduce noise.
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Arnold Chan@slaz
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Hunters
1 month ago
001
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