Detections

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

3,615 detections

Detects M365 Copilot users exhibiting suspicious application usage patterns including multi-location access, abnormally high activity volumes, or access to multiple Copilot applications that may indicate account compromise or automated abuse. The detection aggregates M365 Copilot Graph API events per user, calculating metrics like distinct cities/countries accessed, unique IP addresses, number of different Copilot apps used, and average events per day over the observation period. Users are flagged when they access Copilot from multiple cities (cities_count > 1), generate excessive daily activity (events_per_day > 100), or use more than two different Copilot applications (app_count > 2), which are anomalous patterns suggesting credential compromise or bot-driven abuse.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0075
This rule identifies when a USB removable media device is attached to a Windows host by monitoring modifications to the HKLM\System\CurrentControlSet\Enum\USBSTOR\ registry key. Adversaries and insider threats may use removable media devices for various malicious activities, including initial access, execution, and data exfiltration.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0064
This analytic is used to identify when a USB removable media device is attached to a Windows host. It queries the Endpoint Registry data model to look for modifications to the Windows Portable Device keys HKLM\SOFTWARE\Microsoft\Windows Portable Devices\Devices\ or HKLM\System\CurrentControlSet\Enum\SWD\WPDBUSENUM\. Adversaries and Insider Threats may use removable media devices for several malicious activities, including initial access, execution, and exfiltration.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1054
The analytic detects a process loading the `credui.dll` or `wincredui.dll` module. This detection leverages Sysmon EventCode 7 to identify instances where these DLLs are loaded by processes outside typical system directories. This activity is significant because adversaries often abuse these modules to create fake credential prompts or dump credentials, posing a risk of credential theft. If confirmed malicious, this activity could allow attackers to harvest user credentials, leading to unauthorized access and potential lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0049
Detects the presence of "UWhRC....AAYBAAAA" pattern in command line.
The pattern "1UWhRCAAAAA..BAAAA" is a base64-encoded signature that corresponds to a marshaled CREDENTIAL_TARGET_INFORMATION structure.
Attackers can use this technique to coerce authentication from victim systems to attacker-controlled hosts.
It is one of the strong indicators of a Kerberos coercion attack, where adversaries manipulate DNS records
to spoof Service Principal Names (SPNs) and redirect authentication requests like in CVE-2025-33073.
If you see this pattern in the command line, it is likely an attempt to add spoofed Service Principal Names (SPNs) to DNS records,
or checking for the presence of such records through the `nslookup` command.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
003
The following analytic identifies the execution of RAR utilities to archive files on a system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, GUIDs, and command-line arguments. This activity is significant as threat actors, including red-teamers and malware like DarkGate, use RAR archiving to compress and exfiltrate collected data from compromised hosts. If confirmed malicious, this behavior could lead to the unauthorized transfer of sensitive information to command and control servers, posing a severe risk to data confidentiality and integrity.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1042
KQL Query from file: New Redis RCE Alert: CVE-2025-49844
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
106828
This rule detects the execution of WinRAR (rar.exe or winrar.exe) from a directory that is not its standard installation path (e.g., 'Program Files\WinRAR'). It specifically excludes 'UnRAR.exe' executions and also filters out executions from the Windows temporary directory ('Windows\Temp') to reduce false positives. This behavior can be indicative of an adversary using a portable or custom-dropped version of WinRAR for archiving data prior to exfiltration, or for other malicious purposes.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0014
The following analytic detects processes on macOS systems that are tapping keyboard events, potentially monitoring all keystrokes made by a user. It leverages data from osquery results within the Alerts data model, focusing on specific process names and command lines. This activity is significant as it is a common technique used by Remote Access Trojans (RATs) to log keystrokes, posing a serious security risk. If confirmed malicious, this could lead to unauthorized access to sensitive information, including passwords and personal data, compromising the integrity and confidentiality of the system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0038
The following analytic detects the use of PowerShell scripts to archive files into a temporary folder. It leverages PowerShell Script Block Logging, specifically monitoring for the `Compress-Archive` command targeting the `Temp` directory. This activity is significant as it may indicate an adversary's attempt to collect and compress data for exfiltration. If confirmed malicious, this behavior could lead to unauthorized data access and exfiltration, posing a severe risk to sensitive information and overall network security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1038
The following analytic detects the use of certutil.exe to add a certificate to the Root certificate store using the "-addstore" flag. In this case, the certificate is loaded from a temporary file path (e.g., %TEMP%) or other uncommon locations (e.g. C:\Users\Public\), which is highly suspicious and uncommon in legitimate administrative activity. This behavior may indicate an adversary is installing a malicious root certificate to intercept HTTPS traffic, impersonate trusted entities, or bypass security controls. The use of flags such as -f (force) and -Enterprise, combined with loading .tmp files from user-writable locations, is consistent with post-exploitation activity seen in credential theft and adversary-in-the-middle (AiTM) attacks. This should be investigated immediately, especially if correlated with unauthorized privilege use or prior certificate modifications. You should monitor when new certificates are added to the root store because this store is what your system uses to decide which websites, apps, and software can be trusted. If an attacker manages to add their own certificate there, they can silently intercept encrypted traffic, impersonate trusted websites, or make malicious programs look safe. This means they could steal sensitive data, bypass security tools, and keep access to your system even after other malware is removed.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0040
The following analytic detects the execution of a PowerShell script designed to capture screen images on a host. It leverages PowerShell Script Block Logging to identify specific script block text patterns associated with screen capture activities. This behavior is significant as it may indicate an attempt to exfiltrate sensitive information by capturing desktop screenshots. If confirmed malicious, this activity could allow an attacker to gather visual data from the compromised system, potentially leading to data breaches or further exploitation.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0037
The analytic detects the creation of image files (PNG, JPG, BMP, GIF, TIFF) in the AppData\Roaming folder by processes that also have a file reference in the same folder. This behavior is commonly associated with malware, such as the Remcos RAT, which captures screenshots and stores them in the AppData folder before exfiltrating them to a command-and-control server. If confirmed malicious, this activity could indicate unauthorized data capture and exfiltration, compromising sensitive information and user privacy.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
This analytic detects the creation of specific archived files, 'passff.tar' and 'cookie.tar', which are known indicators of IcedID malware exfiltrating sensitive browser information like history and cookies. The detection leverages Sysmon EventCode 11 to identify these file creations. This activity is critical as it signifies the potential compromise of sensitive user data, which could lead to further exploitation, data breaches, or escalation of attacker presence within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The following analytic detects the creation of archived files in a temporary folder, which may contain collected data. This behavior is often associated with malicious activity, where attackers compress sensitive information before exfiltration. The detection focuses on monitoring specific directories, such as temp folders, for the presence of newly created archive files (e.g., .zip, .rar, .tar). By identifying this pattern, security teams can quickly respond to potential data collection and exfiltration attempts, minimizing the risk of data breaches and improving overall threat detection.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
This YARA rule detects the Veaty backdoor by identifying specific bytecode patterns related to fetching commands, reading mailbox folders, and adding inbox rules. The rule looks for a combination of these patterns within a file that also has a valid MS-DOS executable header (MZ header).
ReversingLabs Yara@ReversingLabsYara
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ReversingLabs Yara
1 year ago
0038
Detects HTTP responses containing JavaScript associated with ClickFix phishing kits. These kits manipulate the DOM to mimic browser verification pages and trick users into copying and executing malicious commands.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
21177
Detects the configuration of a new ISATAP router on a Windows host. While ISATAP is a legitimate Microsoft technology for IPv6 transition, unexpected or unauthorized ISATAP router configurations could indicate a potential IPv6 DNS Takeover attack using tools like mitm6.
In such attacks, adversaries advertise themselves as DHCPv6 servers and set malicious ISATAP routers to intercept traffic.
This detection should be correlated with network baselines and known legitimate ISATAP deployments in your environment.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
001
Detects DNS query requests to "update.onelaunch.com". This domain is associated with the OneLaunch adware application.
When the OneLaunch application is installed it will attempt to get updates from this domain.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
001
Detects command line parameters used by ADCSPwn, a tool to escalate privileges in an active directory network by coercing authenticate from machine accounts and relaying to the certificate service
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
001
Detects the execution of different compiled Windows binaries of the impacket toolset (based on names or part of their names - could lead to false positives)
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
001
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