Detections

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

18,116 detections

Detects outbound network traffic matching XMRig Monero cryptocurrency miner stratum login behavior originating from an internal host.
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Arnold Chan@slaz
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Detection & Hunting Community
21 days ago
003
Detects outbound network traffic matching XMRig Monero cryptocurrency miner stratum login behavior originating from an internal host.
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Arnold Chan@slaz
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Detections.ai Community
21 days ago
003
Builds a per-account baseline of the devices that each enabled service account has made a successful network logon to over the previous 30 days, then alerts when one makes a successful network logon to a device outside that baseline within the latest window.

Service accounts are identified from IdentityInfo using each account’s most recent recorded type and enabled status, and are matched to logon events by their on-premises SID, so local accounts or accounts in other domains that share the same name are not mistaken for them. Accounts with no logon history in the baseline period are still evaluated, so a dormant service account that suddenly begins making network logons will alert on every device it reaches.

Service accounts tend to touch a small, fixed set of hosts, so a per-entity first-seen check is a strong lateral movement signal with less noise than the same logic applied to users.

Each result is enriched with the number of times the destination device’s sensor reporting restarted during the alert window, along with the times of those restarts in UTC, as restarts close to the new logons often indicate maintenance activity such as patching, although they should prompt a check to confirm rather than closure of the alert.

The rule runs every 24 hours, as this is the only Defender custom detection frequency with a 30-day lookback, and the alert window covers the last 25 hours so that a slightly delayed run does not leave a gap.

The baseline and alert windows are separated by ingestion time rather than event time, so events that arrive late are still evaluated.
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Christopher Scott@Scocha
Defender - KQL
16 days ago
000
Detects HTTP traffic associated with the Wazza phishing kit anti-bot mechanism, including token minting requests, signed token responses, and validation checks.
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Arnold Chan@slaz
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Detection & Hunting Community
22 days ago
003
Detects payload staging activity associated with threat actor UAC-0099, correlating the creation or modification of executable/DLL files in disguised LocalAppData directories with decoy images or library configuration files within a one-hour window.
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Arnold Chan@slaz
Defender - KQL
22 days ago
003
Detects a multi-stage process execution chain involving PowerShell: first, a script-based download of remote content, followed by in-memory reflection, and finally, suspicious memory allocation or thread manipulation within the same process context. This pattern is characteristic of fileless malware execution chains designed to evade disk-based detection.
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Arnold Chan@slaz
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Detections.ai Community
27 days ago
4012
The following analytic identifies a Python process being executed where it's process name does not match
it's original file name attribute. Processes that have been renamed and executed may be an indicator that
an adversary is attempting to evade defenses or execute malicious code.
Splunk Security@SplunkSecurity
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Splunk Security Content
24 days ago
205
Detects a successful device-code sign-in whose session is replayed successfully within 60 minutes from a different IP and ASN. Only successful replays count (interrupt codes removed) and Microsoft first-party ASN egress is excluded.
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Arnold Chan@slaz
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Midnight Slayer
19 days ago
001
Detects a successful device-code sign-in whose session is replayed successfully within 60 minutes from a different IP and ASN. Only successful replays count (interrupt codes removed) and Microsoft first-party ASN egress is excluded.
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Arnold Chan@slaz
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Detection & Hunting Community
19 days ago
001
Detects M365 Copilot jailbreak attempts through prompt injection techniques including rule manipulation, system bypass commands, and AI impersonation requests that attempt to circumvent built-in safety controls. The detection searches exported eDiscovery prompt logs for jailbreak keywords like "pretend you are," "act as," "rules=," "ignore," "bypass," and "override" in the Subject_Title field, assigning severity scores based on the manipulation type (score of 4 for amoral impersonation or explicit rule injection, score of 3 for entity roleplay or bypass commands). Prompts with a jailbreak score of 2 or higher are flagged, prioritizing the most severe attempts to override AI safety mechanisms through direct instruction injection or unauthorized persona adoption.
Splunk Security@SplunkSecurity
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Splunk Security Content
23 days ago
003
The following analytic detects the creation of an NTFS alternate data stream (ADS) accessed over a local administrative share targeting the loopback address (127.0.0.1).
It leverages Windows Security Event Logs with EventCode 5145 to identify this activity.
Legitimate local processes access files directly rather than through a local SMB share.
This behavior is a hallmark of the ShieldBreak exploit, which abuses a symbolic link swap through a loopback share to redirect a privileged, Defender-driven write into an alternate data stream on a system-owned file, ultimately landing attacker content in C:\Windows\System32.
If confirmed malicious, this activity indicates an in-progress local privilege escalation attempt and should be investigated immediately.
Splunk Security@SplunkSecurity
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Splunk Security Content
30 days ago
6021
Detects the rare 'AssumeRoot' event in AWS STS followed by high-impact administrative or destructive API calls within a one-hour window. This behavior often indicates an adversary attempting to gain elevated, privileged access to perform unauthorized actions such as disabling logging, deleting infrastructure, or modifying IAM policies.
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ills3c Intel&Coffee@Ills3C
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Detections.ai Community
17 days ago
000
Detects the creation of persistence mechanisms through both Registry Run keys and Scheduled Tasks within a one-hour window, specifically targeting names indicative of masquerading as legitimate update or helper components.
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Ankit Mehta@Secvyn
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SlimKQL
29 days ago
10017
Detects high-risk operations performed by the Entra ID/AAD Connect synchronization service account (e.g., Sync_* or ADToAADSyncServiceAccount). This account, which often holds broad directory permissions, is a prime target for attackers to gain persistence or escalate privileges within the cloud directory. The rule monitors for unauthorized sign-ins, sensitive configuration changes (such as modifications to federation trust, authentication policies, or directory synchronization settings), and password resets targeting the sync account itself.
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Ibrahim Saud@tektrix
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Detections.ai Community
30 days ago
10018
Detects the GOST tunnel binary deployed as svchost.exe from a staging directory, identified by its known hash, or by an unsigned PE importing config.dll with a matching MZ header and embedded config.dll reference (reduces FPs from legitimately signed software that imports a DLL of the same name)
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Arnold Chan@slaz
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Detection & Hunting Community
23 days ago
003
Detects the GOST tunnel binary deployed as svchost.exe from a staging directory, identified by its known hash, or by an unsigned PE importing config.dll with a matching MZ header and embedded config.dll reference (reduces FPs from legitimately signed software that imports a DLL of the same name)
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Arnold Chan@slaz
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Detections.ai Community
23 days ago
003
Detects sign-in activity originating from a known suspicious VPN/proxy IP range targeting critical Microsoft 365 applications. The rule specifically monitors for instances where multi-factor authentication (MFA) enforcement appears to be absent or failed, suggesting a potential account compromise and subsequent data access attempt via a proxy/VPN.
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Ankit Mehta@Secvyn
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SlimKQL 2026
1 month ago
24020
Detects emails from free-mail domains (@mail.com or @outlook.com) that contain a specific malicious infrastructure indicator in the InternetMessageId or originate from a known suspicious IP address associated with TA419-style spoofing campaigns. This indicates the email was relayed through unauthorized infrastructure rather than the expected legitimate mail providers.
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Arnold Chan@slaz
Defender - KQL
26 days ago
007
Detects a shell command referencing a hidden, octal/self-deleting payload
file written to a VMFS datastore volume using a '.sys' filename prefix followed by a
numeric timestamp, combined with an 'rm -f' cleanup of the same file. CrowdStrike observed
this VMFS staging technique used to blend a decoded payload in with legitimate system files
before it is executed and then removed as an anti-forensics step, denying incident
responders a copy of the payload from disk.
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Georg Lauenstein@gsec
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SecOps Signals
20 days ago
001
Detects HTTP traffic associated with the Wazza phishing kit anti-bot mechanism, including token minting requests, signed token responses, and validation checks.
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Arnold Chan@slaz
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Detections.ai Community
22 days ago
002
The following analytic detects the execution of tools commonly exploited by cybercriminals, such as those used for unauthorized access, network scanning, privilege escalation, password dumping or data exfiltration.
It leverages process activity data from Endpoint Detection and Response (EDR) agents, focusing on known attacker tool names.
This activity is significant because it serves as an early warning system for potential security incidents, enabling prompt response. If confirmed malicious, this activity could lead to unauthorized access, data theft, or further network compromise, posing a severe threat to the organization's security infrastructure.
Splunk Security@SplunkSecurity
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Splunk Security Content
25 days ago
105
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