Detections

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

597 detections

The following analytic detects the registration of a new Multi-Factor Authentication (MFA) method for a user account in Azure Active Directory. It leverages Azure AD audit logs to identify changes in MFA configurations. This activity is significant because adding a new MFA method can indicate an attacker's attempt to maintain persistence on a compromised account. If confirmed malicious, the attacker could bypass existing security measures, solidify their access, and potentially escalate privileges, access sensitive data, or make unauthorized changes. Immediate verification and remediation are required to secure the affected account.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1048
The following analytic detects modifications to the SID History attribute in Active Directory by leveraging event code 5136. This detection uses logs from the `wineventlog_security` data source to identify changes to the sIDHistory attribute. Monitoring this activity is crucial as the SID History attribute can be exploited by adversaries to inherit permissions from other accounts, potentially granting unauthorized access. If confirmed malicious, this activity could allow attackers to maintain persistent access and escalate privileges within the domain, posing a significant security risk.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0048
This analytic detects changes to the sIDHistory attribute of user or computer objects within the same domain. It leverages Windows Security Event Codes 4738 (User Account Changed) and 4742 (Computer Account Changed) to identify when the sIDHistory attribute is modified. This activity is significant because the sIDHistory attribute can be abused by adversaries to grant unauthorized access by inheriting permissions from another account. If confirmed malicious, this could allow attackers to maintain persistent access or escalate privileges within the domain, posing a severe security risk. The rule specifically looks for cases where the added SID History matches the target SID or target domain name, indicating an attempt to add a SID from the same domain.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1044
The analytic detects a suspicious computer account name change in Active Directory. It leverages Event ID 4781, which logs account name changes, to identify instances where a computer account name is changed to one that does not end with a '$'. This behavior is significant as it may indicate an attempt to exploit CVE-2021-42278 and CVE-2021-42287, which can lead to domain controller impersonation and privilege escalation. If confirmed malicious, this activity could allow an attacker to gain elevated privileges and potentially control the domain.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0043
The following analytic detects the registration of a new Multi-Factor Authentication (MFA) method for a PingID (PingOne) account. It leverages JSON logs from PingID, specifically looking for successful device pairing events. This activity is significant as adversaries who gain unauthorized access to a user account may register a new MFA method to maintain persistence. If confirmed malicious, this could allow attackers to bypass existing security measures, maintain long-term access, and potentially escalate their privileges within the compromised environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1042
The analytic detects the assignment of high-risk Graph API permissions in Azure AD, specifically Application.ReadWrite.All, AppRoleAssignment.ReadWrite.All, and RoleManagement.ReadWrite.Directory. It scans Azure AD AuditLogs for 'Update application' operations, identifying when these permissions are assigned. This activity grants broad control over Azure AD, including application and directory settings. If malicious, it could lead to unauthorized modifications and potential security breaches, compromising the integrity and security of the Azure AD environment. Immediate investigation is required.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0042
This analytic detects modifications to privileged groups in Active Directory, including creation, deletion, and changes to various types of groups such as local, global, universal, and LDAP query groups. It specifically monitors for changes to high-privilege groups like "Administrators", "Domain Admins", "Enterprise Admins", and "ESX Admins", among others. This detection is particularly relevant in the context of potential exploitation of vulnerabilities like the VMware ESXi Active Directory Integration Authentication Bypass (CVE-2024-37085), where attackers may attempt to manipulate privileged groups to gain unauthorized access to systems.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0042
This analytic detects an increase in modifications to AD user objects. A large volume of changes to user objects can indicate potential security risks, such as unauthorized access attempts, impairing defences or establishing persistence. By monitoring AD logs for unusual modification patterns, this detection helps identify suspicious behavior that could compromise the integrity and security of the AD environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1040
The following analytic detects excessive usage of `net.exe` within a one-minute interval. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line executions. This behavior is significant as it may indicate an adversary attempting to create, delete, or disable multiple user accounts rapidly, a tactic observed in Monero mining incidents. If confirmed malicious, this activity could lead to unauthorized user account manipulation, potentially compromising system integrity and enabling further malicious actions.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0039
The analytic detects the addition of a new owner to a Service Principal within an Azure AD tenant. This activity is significant because Service Principals do not support multi-factor authentication or conditional access policies, making them a target for adversaries seeking persistence or privilege escalation. If confirmed malicious, this activity could allow attackers to maintain access to the Azure AD environment with single-factor authentication, potentially leading to unauthorized access and control over critical resources.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0038
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
0036
The analytic detects an Azure AD user enabling a previously disabled account and resetting its password within 2 minutes. This activity is significant because it may indicate an adversary with administrative access attempting to establish a backdoor identity within the Azure AD tenant. If confirmed malicious, this could allow the attacker to maintain persistent access, escalate privileges, and potentially exfiltrate sensitive information from the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects instances where more than five unique Windows account passwords are changed within a 10-minute interval. It leverages Event Code 4724 from the Windows Security Event Log, using the wineventlog_security dataset to monitor and count distinct TargetUserName values. This behavior is significant as rapid password changes across multiple accounts are unusual and may indicate unauthorized access or internal compromise. If confirmed malicious, this activity could lead to widespread account compromise, unauthorized access to sensitive information, and potential disruption of services.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
This analytic detects an increase in modifications to Active Directory groups or objects. Frequent changes to AD groups or objects can indicate potential security risks, such as unauthorized access attempts, impairing defenses, or establishing persistence. By monitoring AD logs for unusual modification patterns, this detection helps identify suspicious behavior that could compromise the integrity and security of the AD environment. The rule specifically looks for a statistically significant increase in the number of unique objects modified by a source user over a 5-minute span, compared to their historical average and standard deviation.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The following analytic identifies the successful deletion of an IAM group in AWS. It leverages CloudTrail logs to detect `DeleteGroup` events with a success status. This activity is significant as it could indicate potential changes in user permissions or access controls, which may be a precursor to further unauthorized actions. If confirmed malicious, an attacker could disrupt access management, potentially leading to privilege escalation or unauthorized access to sensitive resources. Analysts should review related IAM events, such as recent user additions or new group creations, to assess the broader context.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
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 detects the use of net.exe to update user account policies to set passwords as non-expiring. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving "/maxpwage:unlimited" or "/maxpwage:49710", which achieve a similar outcome theoretically. This activity is significant as it can indicate an attempt to maintain persistence, escalate privileges, evade defenses, or facilitate lateral movement. If confirmed malicious, this behavior could allow an attacker to maintain long-term access to compromised accounts, potentially leading to further exploitation and unauthorized access to sensitive information.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The analytic detects attempts to reset the Directory Services Restore Mode (DSRM) administrator password on a Domain Controller. It leverages event code 4794 from the Windows Security Event Log, specifically looking for events where the DSRM password reset is attempted. This activity is significant because the DSRM account can be used similarly to a local administrator account, providing potential persistence for an attacker. If confirmed malicious, this could allow an attacker to maintain administrative access to the Domain Controller, posing a severe risk to the domain's security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0030
The analytic detects the use of the `net.exe` utility to disable a user account via the command line. This activity is significant as it may indicate an adversary's attempt to disrupt user availability, potentially as a precursor to further malicious actions. If confirmed malicious, this could lead to denial of service for legitimate users, aiding the attacker in maintaining control or covering their tracks.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0028
This rule detects when a user is added to a role in Microsoft Entra ID (formerly Azure AD) outside of a Privileged Identity Management (PIM) process. While adding users to roles is a normal administrative action, performing it outside of PIM can indicate a potential security risk, as PIM provides just-in-time access and approval workflows for privileged roles. This rule specifically looks for "Add member to role outside of PIM (permanent)" events, which are often triggered via PowerShell API calls.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
2 years ago
3040
Detects when a new user is created in Entra ID (formerly Azure Active Directory) and subsequently assigned administrative or other specified roles within a 90-minute window. This rule aims to identify potential privilege escalation or suspicious account setup activities.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
2 years ago
2034
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