Detections

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

123 detections

This rule detects a correlated attack chain involving LDAP Service Principal Name (SPN) enumeration followed by Kerberoasting activity. It identifies an actor performing LDAP queries for SPNs, then links that actor to subsequent Kerberos Ticket-Granting Service (TGS) requests for those service accounts within a defined time window. The rule specifically looks for a minimum number of unique service accounts targeted to trigger an alert, indicating a potential Kerberoasting attack.
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Daniel Miller@dxmiller
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Detections.ai Community
9 months ago
230273
This rule detects attempts to discover Group Policy settings on a Windows system. It identifies the execution of common command-line interpreters (cmd.exe, powershell.exe, wmic.exe, rundll32.exe) followed by specific commands or PowerShell cmdlets used for GPO enumeration. This includes native Windows commands like 'gpresult' and 'secedit', registry queries for policy settings, and PowerShell cmdlets such as 'Get-GPO' and 'Get-GPResultantSetOfPolicy'. Additionally, it looks for LDAP-related commands or patterns ('ldapsearch', 'groupPolicyContainer') that might indicate GPO discovery via directory services. The rule also correlates these process events with network connections to SYSVOL shares or LDAP ports (389, 636) to further confirm GPO-related activity.
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Awais Munir@iawais
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Detections.ai Community
10 months ago
863525
This rule detects attempts to discover Group Policy settings on a system. It identifies the execution of common command-line interpreters (cmd.exe, powershell.exe, wmic.exe, rundll32.exe) followed by specific commands or PowerShell cmdlets used for GPO enumeration. This includes native Windows commands like 'gpresult' and 'secedit', registry queries for policy settings, PowerShell cmdlets such as 'Get-GPO' and 'Get-GPResultantSetOfPolicy', and LDAP-related queries for 'groupPolicyContainer'. Additionally, it correlates these process events with network connections to SYSVOL shares or LDAP ports (389, 636) that also contain 'groupPolicyContainer' in the URL, indicating potential GPO access. The rule filters out common system processes to reduce noise.
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Awais Munir@iawais
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Detections.ai Community
11 months ago
0078
Detects any authentication activity (successful or failed) for emergency break-glass administrative accounts
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Alex Acosta@razerTos71
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Detections.ai Community
11 months ago
280377
Detects an NTLM authentication attempt with an empty username field. This is a key indicator of the NTLM LDAP authentication bypass vulnerability (CVE-2025-54918), where an attacker coerces a SYSTEM account authentication and relays it to LDAP.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
20179
The following analytic detects the use of default or publicly known named pipes associated with Cobalt Strike. It leverages Sysmon EventID 17 and 18 to identify specific named pipes commonly used by Cobalt Strike's Artifact Kit and Malleable C2 Profiles. This activity is significant because Cobalt Strike is a popular tool for adversaries to conduct post-exploitation tasks, and identifying its named pipes can reveal potential malicious activity. If confirmed malicious, this could indicate an active Cobalt Strike beacon, leading to unauthorized access, data exfiltration, or further lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
100247
This analytic detects suspicious data transfer activities involving the use of the `split` syscall with the `-b` option, which specifies the size of each output file. This technique can be used by attackers to evade detection by breaking large files into smaller parts, bypassing size-based security controls, and facilitating covert exfiltration of sensitive data. By monitoring for unusual or unauthorized use of the `split` syscall with a specified block size, this analytic helps identify potential data exfiltration attempts.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0087
This analytic identifies the bulk creation of ransomware notes (e.g., .txt, .html, .hta files) on an infected machine. It leverages Sysmon EventCode 11 to detect multiple instances of these file types being created within a short time frame (10 seconds). A detection is triggered if 15 or more unique readme paths are observed. This activity is a strong indicator of an active ransomware attack, where the attacker is notifying the victim of the encryption. If confirmed malicious, this behavior could lead to widespread data encryption, rendering critical files inaccessible and potentially causing significant operational disruption.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1160
The following analytic detects suspicious attempts to find credentials stored in password stores, indicating a potential attacker's effort to access sensitive login information. Password stores are critical repositories that contain valuable credentials, and unauthorized access to them can lead to significant security breaches. By monitoring for unusual or unauthorized activities related to password store access, this analytic helps identify potential credential theft attempts, allowing security teams to respond promptly and prevent unauthorized access to critical systems and data.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0056
This analytic detects the configuration of TFTP services on Cisco IOS devices that could be used to exfiltrate sensitive configuration files. Threat actors like Static Tundra have been observed configuring TFTP servers to make device configuration files accessible for exfiltration after gaining initial access. The detection specifically looks for commands that expose critical configuration files such as startup-config, running-config, and other sensitive system information through TFTP. This activity is particularly concerning as it may represent an attempt to steal credentials, network topology information, and other sensitive data stored in device configurations.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1059
Detects a successful NTLM network logon from a NULL SID (S-1-0-0). This pattern is a strong indicator of an NTLM relay attack, where an attacker intercepts an authentication attempt and relays it to a target service, such as LDAP on a Domain Controller, to perform actions on behalf of the relayed user. This is often used to modify Group Policy Objects (GPOs).
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R W@shiftyroot
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Detections.ai Community
1 year ago
73259
No description available.
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
115121
Detects potential DCSync attacks by identifying Event ID 4662 where specific DS-Replication access rights are used by a non-domain controller. This rule specifically looks for attempts to replicate directory changes (DS-Replication-Get-Changes, DS-Replication-Get-Changes-All, DS-Replication-Get-Changes-In-Filtered-Set) from an IP address that is not a known domain controller, while also excluding common system accounts.
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R W@shiftyroot
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Detections.ai Community
1 year ago
123120
The following analytic identifies the addition and quick deletion of a Service Principal Name (SPN) to a domain account within 5 minutes. This detection leverages EventCode 5136 from the Windows Security Event Log, focusing on changes to the servicePrincipalName attribute. This activity is significant as it may indicate an attempt to perform Kerberoasting, a technique used to crack the cleartext password of a domain account offline. If confirmed malicious, this could allow an attacker to gain unauthorized access to sensitive information or escalate privileges within the domain environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0048
Detects potential Active Directory enumeration via LDAP. This rule identifies suspicious LDAP search filters and distinguished name enumerations that are commonly used by reconnaissance tools like PowerView and SharpHound to gather information about users, groups, computers, and domain trusts within an Active Directory environment. The rule specifically looks for various 'groupType', 'sAMAccountType', 'objectCategory', 'objectClass', 'primaryGroupID', 'userAccountControl' attributes, and specific distinguished names or flags that indicate detailed AD reconnaissance.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
4080
KQL Query from file: Sentinel KQL Detection for ShadowHound
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
60224
KQL Query from file: DefenderXDR LDAP Enumeration Detection
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
101129
KQL Query from file: LDAPNightmare POC Detection
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
2189
The following analytic detects the creation of a new Group Policy Object (GPO) using Splunk's Admon data. It identifies events where a new GPO is created, excluding default "New Group Policy Object" entries. Monitoring GPO creation is crucial as adversaries can exploit GPOs to escalate privileges or deploy malware across an Active Directory network. If confirmed malicious, this activity could allow attackers to control system configurations, deploy ransomware, or propagate malware, significantly compromising the network's security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1042
This analytic detects modifications to the default Group Policy Objects (GPOs) in an Active Directory environment. It leverages Splunk's Admon to monitor updates to the "Default Domain Policy" and "Default Domain Controllers Policy." This activity is significant because changes to these default GPOs can indicate an adversary with privileged access attempting to gain further control, establish persistence, or deploy malware across multiple hosts. If confirmed malicious, such modifications could lead to widespread policy enforcement changes, unauthorized access, and potential compromise of the entire domain environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1038
The following analytic detects the execution of the `Get-DomainGroup` cmdlet using PowerShell Script Block Logging (EventCode=4104). This cmdlet, part of the PowerView tool, is used to enumerate domain groups within a Windows domain. The detection leverages script block text to identify this specific command. Monitoring this activity is crucial as it may indicate an adversary or Red Team performing reconnaissance to gain situational awareness and map out Active Directory structures. If confirmed malicious, this activity could lead to further exploitation, including privilege escalation and lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0029
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