Detections

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

170 detections

This rule detects modifications to the "DsrmAdminLogonBehavior" registry value. Attackers may modify this value to abuse the Directory Services Restore Mode (DSRM) administrator account for persistence and access to Active Directory. The DSRM account is a local administrator account on a Domain Controller, typically used for restoring AD backups or recovering from failures. By changing "DsrmAdminLogonBehavior" from its default value of '0' (only usable in DSRM) to '1' (usable when AD DS service is stopped) or '2' (always usable), attackers can gain persistent access to the Domain Controller outside of DSRM, facilitating credential access and defense evasion.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0014
This analytic detects the creation or modification of network interfaces on Cisco devices, which could indicate an attacker establishing persistence or preparing for lateral movement. After gaining initial access to network devices, threat actors like Static Tundra often create new interfaces (particularly loopback interfaces) to establish covert communication channels or maintain persistence. This detection specifically looks for the configuration of new interfaces, interface state changes, and the assignment of IP addresses to interfaces. These activities are particularly concerning when they involve unusual interface names or descriptions containing suspicious terms.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5058
Detects suspicious OAuth app consents, role assignments, and group changes involving Workday and Salesforce, indicating potential account compromise or privilege escalation.
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Tun Tun Naing@tuntun
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Detections.ai Community
1 year ago
80180
This detection rule flags events where conditional access policies are getting weaker, when modifications to CA inclusion or exclusion groups are happening, or when the effectiveness of a policy is disabled.
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Robbe Van den Daele@RobbeVdDaele
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Detections.ai Community
1 year ago
70118
The analytic identifies the deletion or modification of registry keys that disable Local Security Authority (LSA) protection and Microsoft Defender Device Guard. This activity is significant because disabling these defenses can leave a system vulnerable to various attacks, including credential theft and unauthorized code execution. If confirmed malicious, this action could allow attackers to bypass critical security mechanisms, leading to potential system compromise and persistent access.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0044
The analytic detects when a Duo policy is created or updated to allow network-based bypass of two-factor authentication (2FA). It identifies this behavior by searching Duo administrator logs for policy creation or update actions where the networks_allow field is present, indicating that specific networks have been permitted to bypass 2FA requirements. This is achieved by parsing the event description and filtering for relevant policy changes, then aggregating the results by user and administrator details. Detecting this behavior is critical for a Security Operations Center (SOC) because allowing network-based 2FA bypass can significantly weaken authentication controls, potentially enabling unauthorized access if a trusted network is compromised or misconfigured. Attackers or malicious insiders may exploit this policy change to circumvent 2FA protections, increasing the risk of account takeover and lateral movement within the environment. Prompt detection enables SOC analysts to investigate and respond to potentially risky policy modifications before they can be leveraged for malicious purposes.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
2090
The analytic identifies Cisco Duo admin login attempts originating from operating systems that are unusual for the environment, specifically excluding commonly used OS like Mac OS X. It analyzes Duo activity logs for 'admin_login' actions and filters out expected operating systems. The rule then aggregates events by browser, version, source IP, location, and OS details to highlight anomalies. Detecting admin logins from unexpected operating systems is crucial for a Security Operations Center (SOC) as it may indicate credential compromise, unauthorized access, or attacker activity using unfamiliar devices. Such behavior can precede privilege escalation, policy changes, or other malicious actions within the Duo environment. Early detection enables rapid investigation and response, reducing the risk of account takeover and minimizing potential damage to organizational security controls.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5068
The analytic detects instances where a Duo user's status is changed to "Bypass" for 2FA, specifically when the previous status was "Active." This behavior is identified by analyzing Duo activity logs for user update actions, extracting the status transitions, and filtering for cases where a user is set to bypass multi-factor authentication. This is a critical event for a Security Operations Center (SOC) to monitor, as bypassing 2FA significantly weakens account security and may indicate malicious insider activity or account compromise. Attackers or unauthorized administrators may exploit this change to disable strong authentication controls, increasing the risk of unauthorized access to sensitive systems and data. Early detection of such changes enables rapid investigation and response, helping to prevent potential breaches and limit the impact of credential-based attacks.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0064
The analytic identifies instances where a Duo administrator creates or updates a policy to allow the use of outdated Flash components, specifically by detecting policy changes with the `flash_remediation=no remediation` attribute. This behavior is significant because permitting old Flash increases the attack surface due to known vulnerabilities. Attackers may exploit such policy changes to bypass security controls, introduce malware, or escalate privileges. Detecting these modifications helps prevent potential exploitation and reduces organizational risk. Immediate investigation is recommended to determine if the change was authorized or indicative of malicious activity.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1049
The analytic identifies instances where a Duo admin logs in using a browser other than Chrome, which is considered unusual based on typical access patterns. This behavior is significant for a SOC because the use of an unexpected browser may indicate credential compromise, session hijacking, or the use of unauthorized devices by attackers attempting to evade detection. Detecting such anomalies enables early investigation and response, helping to prevent privilege escalation, policy manipulation, or further compromise of sensitive administrative accounts. The impact of this attack could include unauthorized changes to security policies, user access, or the disabling of critical security controls, posing a substantial risk to the organizations security posture.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
3053
The following analytic detects when a Duo policy is created or updated to allow access without two-factor authentication (2FA) for users in countries other than the default. It identifies this behavior by searching Duo administrator activity logs for policy creation or update actions where the policy description indicates that access is permitted without 2FA for certain user locations. This is achieved by parsing the relevant fields in the logs and filtering for the specific condition of 'Allow access without 2FA.' This behavior is significant for a Security Operations Center (SOC) because bypassing 2FA for any user group or location weakens the organization's security posture and increases the risk of unauthorized access. Attackers or malicious insiders may exploit such policy changes to circumvent strong authentication controls, potentially leading to account compromise, data breaches, or lateral movement within the environment. Early detection of these policy modifications enables the SOC to investigate and respond before attackers can leverage the weakened controls, thereby reducing the risk and impact of a successful attack.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0040
The following analytic identifies instances where a Duo administrator creates or updates a policy to explicitly deny user access within the Duo environment. It detects this behavior by searching Duo administrator activity logs for policy creation or update actions where the authentication status is set to "Deny access." By correlating these events with user and admin details, the analytic highlights potential misuse or malicious changes to access policies. This behavior is critical for a SOC to monitor, as unauthorized or suspicious denial of access policies can indicate insider threats, account compromise, or attempts to disrupt legitimate user access. The impact of such an attack may include denial of service to critical accounts, disruption of business operations, or the masking of further malicious activity by preventing targeted users from accessing resources. Early detection enables rapid investigation and remediation to maintain organizational security and availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1040
The analytic detects when a Duo policy is created or updated to allow devices without a screen lock requirement. It identifies this behavior by searching Duo administrator activity logs for policy creation or update events where the 'require_lock' setting is set to false. This action may indicate a weakening of device security controls, potentially exposing the organization to unauthorized access if devices are lost or stolen. For a Security Operations Center (SOC), identifying such policy changes is critical, as attackers or malicious insiders may attempt to lower authentication standards to facilitate unauthorized access. The impact of this attack could include increased risk of credential compromise, data breaches, or lateral movement within the environment due to reduced device security requirements.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0037
The analytic detects when a Duo policy is created or updated to allow tampered or rooted devices, such as jailbroken smartphones, to access protected resources. It identifies this behavior by searching Duo administrator activity logs for policy changes where the allow_rooted_devices setting is enabled. This is accomplished by filtering for policy creation or update actions and parsing the policy description for the relevant configuration. Allowing tampered devices poses a significant security risk, as these devices may bypass built-in security controls, run unauthorized software, or be more susceptible to compromise. For a Security Operations Center (SOC), identifying such policy changes is critical because it may indicate either a misconfiguration or a malicious attempt to weaken authentication requirements, potentially enabling attackers to access sensitive systems with compromised devices. The impact of this attack can include unauthorized access, data breaches, and lateral movement within the environment, making prompt detection and response essential to maintaining organizational security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
KQL Query from file: GraphRunner Recon Detection & Response
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
61354
KQL Query
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
150138
KQL Query from file: NEW Real-time Anomalous Token Detection
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
50131
KQL Query from file: Entra Passkey Addition Threat Detection
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
7092
KQL Query from file: Detecting High Risk Passkey Users
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
3090
KQL Query from file: Entra ID Administrative Role (AD-Sync)
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
6083
KQL Query from file: Threat Hunting BYOVD Scenarios
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Steven Lim@KQLWizard
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SlimKQL
1 year ago
6083
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