Detections

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

4,308 detections

The following analytic detects the resetting of the master user password for an Amazon RDS DB instance. It leverages AWS CloudTrail logs to identify events where the `ModifyDBInstance` API call includes a new `masterUserPassword` parameter. This activity is significant because unauthorized password resets can grant attackers access to sensitive data stored in production databases, such as credit card information, PII, and healthcare data. If confirmed malicious, this could lead to data breaches, regulatory non-compliance, and significant reputational damage. Immediate investigation is required to determine the legitimacy of the password reset.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The analytic detects an AWS account experiencing more than 20 failed authentication attempts within a 5-minute window. It leverages AWS CloudTrail logs to identify multiple failed ConsoleLogin events. This behavior is significant as it may indicate a brute force attack targeting the account. If confirmed malicious, the attacker could potentially gain unauthorized access, leading to data breaches or further exploitation of the AWS environment. Security teams should consider adjusting the threshold based on their specific environment to reduce false positives.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The analytic detects an AWS CloudTrail event where a user with permissions updates the login profile of another user. It leverages CloudTrail logs to identify instances where the user making the change is different from the user whose profile is being updated. This activity is significant because it can indicate privilege escalation attempts, where an attacker uses a compromised account to gain higher privileges. If confirmed malicious, this could allow the attacker to escalate their privileges, potentially leading to unauthorized access and control over sensitive resources within the AWS environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The analytic identifies a single source IP failing to authenticate with multiple valid users, potentially indicating a Password Spraying attack against an Azure Active Directory tenant. It uses Azure SignInLogs data and calculates the standard deviation for source IPs, applying the 3-sigma rule to detect unusual numbers of failed authentication attempts. This activity is significant as it may signal an adversary attempting to gain initial access or elevate privileges. If confirmed malicious, this could lead to unauthorized access, privilege escalation, and potential compromise of sensitive information.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The following analytic detects the execution of the `Get-AdUser` PowerShell cmdlet, which is used to enumerate all domain users. It leverages PowerShell Script Block Logging (EventCode=4104) to identify instances where this command is executed with a filter. This activity is significant as it may indicate an attempt by adversaries or Red Teams to gather information about domain users for situational awareness and Active Directory discovery. If confirmed malicious, this behavior could lead to further reconnaissance and potential exploitation of user accounts within the domain.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
The analytic identifies processes with command-line parameters associated with web browser credential dumping tools, specifically targeting behaviors used by Remcos RAT malware. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and specific file paths. This activity is significant as it indicates potential credential theft, a common tactic in broader cyber-espionage campaigns. If confirmed malicious, attackers could gain unauthorized access to sensitive web credentials, leading to further system compromise and data breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
This analytic detects a computer account requesting a Kerberos ticket, which is unusual as typically user accounts request these tickets. This detection leverages Windows Security Event Logs, specifically EventCode 4768, to identify instances where the TargetUserName ends with a dollar sign ($), indicating a computer account. This activity is significant because it may indicate the use of tools like KrbUpRelay or other Kerberos-based attacks. If confirmed malicious, this could allow attackers to impersonate computer accounts, potentially leading to unauthorized access and lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
The analytic detects the addition of Service Principal Names (SPNs) HOST and RestrictedKrbHost to a computer account, indicative of KrbRelayUp behavior. This detection leverages Windows Security Event Logs, specifically EventCode 4741, to identify changes in SPNs. This activity is significant as it is commonly associated with Kerberos-based attacks, which can be used to escalate privileges or perform lateral movement within a network. If confirmed malicious, this behavior could allow an attacker to impersonate services, potentially leading to unauthorized access to sensitive resources.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The following analytic detects the execution of the Windows OS tool cmdkey.exe, which is used to create stored usernames, passwords, or credentials. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs and command-line arguments. This activity is significant because cmdkey.exe is often abused by post-exploitation tools and malware, such as Darkgate, to gain unauthorized access. If confirmed malicious, this behavior could allow attackers to escalate privileges and maintain persistence on the targeted host, facilitating further attacks and potential data breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The analytic detects the execution of the `Find-InterestingDomainAcl` cmdlet, which is part of the PowerView toolkit. This cmdlet is used to identify misconfigured or unusual Access Control Lists (ACLs) within a domain. Adversaries may use this to find privilege escalation opportunities or weak security configurations in Active Directory, potentially leading to unauthorized access or further exploitation.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
This analytic identifies a single source user failing to authenticate with more than 30 unique target users using explicit credentials on a host. It leverages Windows Event 4648, which is generated when a process attempts an account logon by explicitly specifying account credentials. This detection is significant as it may indicate a Password Spraying attack, where an adversary attempts to gain initial access or elevate privileges within an Active Directory environment. If confirmed malicious, this activity could lead to unauthorized access, privilege escalation, and potential compromise of sensitive information.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The following analytic identifies the creation of AWS IAM access keys by a user for another user, which can indicate privilege escalation. It leverages AWS CloudTrail logs to detect instances where the user creating the access key is different from the user for whom the key is created. This activity is significant because unauthorized access key creation can allow attackers to establish persistence or exfiltrate data via AWS APIs. If confirmed malicious, this could lead to unauthorized access to AWS services, data exfiltration, and long-term persistence in the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic identifies the execution of tools built by NirSoft by detecting specific command-line arguments such as "/stext" and "/scomma". It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line executions. This activity is significant because NirSoft tools, while legitimate, can be exploited by attackers for malicious purposes such as credential theft or system reconnaissance. If confirmed malicious, this activity could lead to unauthorized access, data exfiltration, or further compromise of the affected system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic detects attempts to access the SAM, SYSTEM, or SECURITY database files within the `windows\system32\config` directory using Windows Security EventCode 4663. This detection leverages Windows Security Event logs to identify unauthorized access attempts. Monitoring this activity is crucial as it indicates potential credential access attempts, possibly exploiting vulnerabilities like CVE-2021-36934. If confirmed malicious, an attacker could extract user passwords, leading to unauthorized access, privilege escalation, and further compromise of the system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
9032
This analytic identifies when the Security Identifier (SID) of a privileged user is added to the SID History attribute of another user account in Active Directory. It specifically looks for Windows Security Event Codes 4742 (A computer account was changed) and 4738 (A user account was changed), combined with identity lookups to determine if the added SID belongs to a privileged account. This activity is critical as it can indicate an attempt to abuse SID history for unauthorized access, privilege escalation, or persistent access within an environment, posing a significant security risk.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic identifies the creation and quick deletion of a Domain Controller (DC) object within 30 seconds in an Active Directory environment, indicative of a potential DCShadow attack. This detection leverages Windows Security Event Codes 5137 and 5141, analyzing the duration between these events. This activity is significant as DCShadow allows attackers with privileged access to register a rogue DC, enabling unauthorized changes to AD objects, including credentials. If confirmed malicious, this could lead to unauthorized AD modifications, compromising the integrity and security of the entire domain.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
This analytic detects the creation of a Windows service named "KrbSCM" which is associated with the KrbRelayUp tool. KrbRelayUp is known for its use in privilege escalation attacks. The detection relies on Windows System Event Log EventCode 7045, which logs service creation events. Identifying this activity is crucial as it indicates a potential privilege escalation attempt that could lead to unauthorized access to sensitive systems and data.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The analytic detects `CertUtil.exe` performing a backup of the Certificate Store. This activity is significant because it may indicate an attempt to steal authentication certificates, which are critical for secure communications. If confirmed malicious, an attacker could use the stolen certificates to impersonate users, decrypt sensitive data, or gain unauthorized access to systems, leading to severe security breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic detects the use of the PowerShell cmdlet 'export-certificate' executed via the command line, indicating an attempt to export a certificate from the local Windows Certificate Store. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs and command-line arguments. Exporting certificates is significant as it may indicate credential theft or preparation for man-in-the-middle attacks. If confirmed malicious, this activity could allow an attacker to impersonate users, decrypt sensitive communications, or gain unauthorized access to systems and data.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The analytic detects the use of the PowerShell cmdlet `Export-PfxCertificate` on the command line, indicating an attempt to export a certificate from the local Windows Certificate Store. This activity is significant as it may indicate an attempt to exfiltrate authentication certificates, which can be used to impersonate users or decrypt sensitive data. If confirmed malicious, this could lead to unauthorized access and potential data breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic identifies the execution of a randomly named binary via `services.exe`, indicative of privilege escalation using Cobalt Strike's `svc-exe`. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process lineage and command-line executions. This activity is significant as it often follows initial access, allowing adversaries to escalate privileges and establish persistence. If confirmed malicious, this behavior could enable attackers to execute arbitrary code, maintain long-term access, and potentially move laterally within the network, posing a severe threat to the organization's security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0031
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