Detections

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

11,831 detections

The following analytic detects the modification of firewall settings to allow file and printer sharing. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving 'netsh' commands that enable file and printer sharing. This activity is significant because it can indicate an attempt by ransomware to discover and encrypt files on additional machines connected to the compromised host. If confirmed malicious, this could lead to widespread file encryption across the network, significantly increasing the impact of a ransomware attack.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0047
The following analytic identifies the execution of rundll32.exe with the DLL function names "Start" and "StartW," commonly associated with Cobalt Strike payloads. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process metadata. This activity is significant as it often indicates the presence of malicious payloads, such as Cobalt Strike, which can lead to unauthorized code execution. If confirmed malicious, this activity could allow attackers to inject shellcode, escalate privileges, and maintain persistence within the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1047
The following analytic detects a suspicious modification to the firewall to allow network discovery on a machine. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving the 'netsh' command to enable network discovery. This activity is significant because it is commonly used by ransomware, such as REvil and RedDot, to discover and compromise additional machines on the network. If confirmed malicious, this could lead to widespread file encryption across multiple hosts, significantly amplifying the impact of the ransomware attack.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0046
The analytic detects AMOS Stealer VM check activity on macOS. It identifies the execution of the "osascript" command along with specific commandline strings that include "set", "system_profiler", and either "VMware" or "QEMU". This activity is indicative of AMOS stealer attempting to determine if it is running within a virtual machine environment. If confirmed malicious, this behavior suggests the host is infected by the AMOS stealer, which could lead to arbitrary code execution, privilege escalation, information theft, or persistence, posing a significant security risk.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0045
This detection identifies potential abuse of SSH ProxyCommand by monitoring for suspicious process execution patterns. Specifically, it looks for instances where ssh.exe (as a parent process) containing "ProxyCommand" in its arguments spawns potentially malicious child processes like mshta, powershell, wscript, or cscript, or processes containing "http" in their command line. This technique can be used by attackers to execute arbitrary commands through SSH proxy configurations, potentially enabling command & control activities or remote code execution. The detection focuses on commonly abused Windows scripting engines and web requests that may indicate malicious activity when spawned through SSH proxy commands.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0045
The following analytic detects suspicious attempts to find SSH private keys, which may indicate an attacker's effort to compromise secure access to systems. SSH private keys are essential for secure authentication, and unauthorized access to these keys can enable attackers to gain unauthorized access to servers and other critical infrastructure. By monitoring for unusual or unauthorized searches for SSH private keys, this analytic helps identify potential threats to network security, allowing security teams to quickly respond and safeguard against unauthorized access and potential breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0044
The following analytic detects the execution of suspicious command-line arguments commonly associated with Conti ransomware, specifically targeting local drives and network shares for encryption. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs that include command-line details. This activity is significant because it indicates a potential ransomware attack, which can lead to widespread data encryption and operational disruption. If confirmed malicious, the impact could be severe, resulting in data loss, system downtime, and potential ransom demands.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0043
Detects PowerShell processes executing commands that utilize `Net.WebClient` to download content, indicated by the presence of `new-object`, `net.webclient).`, and `download` keywords in the command line, along with either `string(` or `file(`. This pattern is commonly used by adversaries for ingress tool transfer or to fetch additional malicious payloads.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1016
This rule detects the use of various command-line tools and PowerShell cmdlets that can initiate web requests. These include native Windows PowerShell cmdlets like 'Invoke-RestMethod', 'Invoke-WebRequest', 'Resume-BitsTransfer', 'Start-BitsTransfer', and their aliases ('irm', 'iwr'), as well as common command-line utilities like 'curl' and 'wget', and .NET framework calls such as '[System.Net.WebRequest]::create' and 'WinHttp.WinHttpRequest'. Adversaries often use these methods to download additional tools, malware, or exfiltrate data from a compromised system.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1016
The analytic detects FTP connections initiated by processes located in non-standard installation paths on Windows systems. It leverages Sysmon EventCode 3 to identify network connections where the process image path does not match common directories like "Program Files" or "Windows\System32". This activity is significant as FTP is often used by adversaries and malware, such as AgentTesla, for Command and Control (C2) communications to exfiltrate stolen data. If confirmed malicious, this could lead to unauthorized data transfer, exposing sensitive information and compromising the integrity of the affected host.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0042
Detects the removal or modification of system firewall rules using common Linux firewall management tools like iptables, firewall-cmd, ufw, and nft. This rule specifically looks for commands that delete or remove existing rules, which adversaries might use to bypass network controls and enable C2 communications, lateral movement, or data exfiltration. This detection aims to catch more granular firewall modifications than just a complete firewall disablement.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
3136
The following analytic detects the modification of SSH Authorized Keys on Linux systems. It leverages process execution data from Endpoint Detection and Response (EDR) agents, specifically monitoring commands like "bash" and "cat" interacting with "authorized_keys" files. This activity is significant as adversaries often modify SSH Authorized Keys to establish persistent access to compromised endpoints. If confirmed malicious, this behavior could allow attackers to maintain unauthorized access, bypassing traditional authentication mechanisms and potentially leading to further exploitation or data exfiltration.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1039
This analytic detects the use of the `taskkill` command to terminate common browser processes (Chrome, Edge, Firefox, Brave, Opera, Chromium). This technique is often employed by malware, such as the Braodo stealer, to close browsers and unlock files containing sensitive information like credentials. Detecting such activity helps security teams investigate and prevent credential theft and system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0038
The following analytic detects the execution of an arbitrary DLL by the Windows Remote Auto Dialer (rasautou.exe). This behavior is identified by analyzing process creation events where rasautou.exe is executed with specific command-line arguments. This activity is significant because it leverages a Living Off The Land Binary (LOLBin) to execute potentially malicious code, bypassing traditional security controls. If confirmed malicious, this technique could allow an attacker to execute arbitrary code, potentially leading to system compromise, privilege escalation, or persistent access within the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
Detects attempts to harvest credentials by enabling the RemoteRegistry service or dumping the SAM, SECURITY, or SYSTEM registry hives, which are behaviors associated with the Flax Typhoon APT group.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
3184
This analytic identifies processes launching netsh.exe, a command-line utility used to modify network configurations. It detects this activity by analyzing data from Endpoint Detection and Response (EDR) agents, focusing on process GUIDs, names, parent processes, and command-line executions. This behavior is significant because netsh.exe can be exploited to execute malicious helper DLLs, serving as a persistence mechanism. If confirmed malicious, an attacker could gain persistent access, modify network settings, and potentially escalate privileges, posing a severe threat to the network's integrity and security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
Detects the execution of a renamed Microsoft Console Debugger (cdb.exe), a technique observed being used by the Jewelbug APT group for defense evasion and execution.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
0050
The analytic detects the use of Wake-on-LAN commands associated with Ryuk ransomware. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific process and command-line activities. This behavior is significant as Ryuk ransomware uses Wake-on-LAN to power on devices in a compromised network, increasing its encryption success rate. If confirmed malicious, this activity could lead to widespread ransomware encryption across multiple endpoints, causing significant operational disruption and data loss. Immediate isolation and thorough investigation of the affected endpoints are crucial to mitigate the impact.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic detects the execution of gpupdate.exe without any command line arguments. This behavior is identified using data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs. It is significant because gpupdate.exe typically runs with specific arguments, and its execution without them is often associated with malicious activities, such as those performed by Cobalt Strike. If confirmed malicious, this activity could indicate an attempt to execute unauthorized commands or scripts, potentially leading to further system compromise or lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1032
The analytic detects the execution of rundll32.exe without any command line arguments. This behavior is identified using Endpoint Detection and Response (EDR) telemetry, focusing on process execution logs. It is significant because rundll32.exe typically requires command line arguments to function properly, and its absence is often associated with malicious activities, such as those performed by Cobalt Strike. If confirmed malicious, this activity could indicate an attempt to execute arbitrary code, potentially leading to credential dumping, unauthorized file writes, or other malicious actions.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The analytic detects potential exploitation of the CrushFTP authentication bypass vulnerability (CVE-2025-31161). This detection identifies suspicious command execution patterns associated with exploitation of this vulnerability, such as executing mesch.exe with specific arguments like b64exec or fullinstall. This activity is indicative of an attacker exploiting CVE-2025-31161 to gain unauthorized access to the CrushFTP server and perform post-exploitation activities.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1030
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