Detections

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

3,141 detections

Detects high-impact phishing campaigns identified by Microsoft Defender for Office 365. Alerts when a campaign (CampaignName, CampaignId) targets 25 or more recipients (RecipientEmailAddress) within 48 hours, providing timestamp and message details (NetworkMessageId) for investigation.
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Andre Zeemering@Azeemering
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Detections.ai Community
8 months ago
9082
This rule identifies accounts receiving the most email and highest threat exposure by analyzing inbound email events. It counts total emails, delivered emails, junked emails, blocked emails, and specifically highlights emails with detected threats (Phish, Malware, Spam) that were successfully delivered to the user's inbox. The output is sorted to prioritize accounts with the highest number of delivered threats.
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Nicholas Isakson@nisakson2000
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Detections.ai Community
8 months ago
2045
This rule detects suspicious user-agent strings in Microsoft Graph activity logs that are commonly associated with reconnaissance and attack tools targeting Azure AD and Microsoft 365 environments. These tools include BloodHound, ROADtools, AADInternals, and various other utilities used for enumeration, credential spraying, and other malicious activities.
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Information hacker@Informationhacker
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Detections.ai Community
9 months ago
350413
Domains that introduce substitutions, extra characters, or randomness (e.g., micr0soft, paypa1-secure) tend to have higher entropy than the original brand name. This increase in entropy is a useful signal for detecting typosquatting and brand impersonation attempts in phishing campaigns.
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Sergio Albea@Sergio_Albea
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01 | 🇨🇭 Swiss Cyber Hunters
9 months ago
130118
Detects the creation or modification of Exchange inbox rules that move messages to potentially risky folders (e.g., Deleted Items, Junk Email, RSS Feeds, Archive, Clutter) or are configured to delete messages. This behavior can be indicative of an attacker attempting to hide malicious emails, exfiltrate data, or disrupt email flow.
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Information hacker@Informationhacker
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Detections.ai Community
9 months ago
161215
https://www.kaseya.com/blog/dkim-replay-attacks-apple-paypal-invoice-abuse/
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Steven Lim@KQLWizard
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SlimKQL 2026
9 months ago
400265
Detects anomalous Exchange Transport Rule activity: high volume changes, suspicious patterns, or after-hours modifications
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nomit vyas@xoxo
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Detections.ai Community
9 months ago
5075
Detects file access or download activity from SharePoint or OneDrive where the user agent is PowerShell. This TTP has been associated with UNC6671 (related to ShinyHunters) for data exfiltration from SaaS applications.
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nomit vyas@xoxo
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Detections.ai Community
9 months ago
150171
This rule detects potential phishing activity by identifying inbound emails from specific sender addresses that were not blocked by Microsoft Defender for Office (MDO), followed by network connections to a known malicious infrastructure associated with 'Tycoon2FA'. The rule first looks for unblocked emails from 'donotreply@docmagic.com' and 'noreply@frigoarrobba.com.br'. If such emails are found, it then checks for network connections to 'listener.facraivo.sa.com' within a 7-day window, indicating a potential compromise or user interaction with the phishing attempt.
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Steven Lim@KQLWizard
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SlimKQL 2026
9 months ago
251259
Detects file access or download operations from Microsoft SharePoint Online where the User-Agent string indicates the use of PowerShell. This behavior has been observed in campaigns by threat groups for bulk data exfiltration.
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g host@ghosty
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Detections.ai Community
9 months ago
242358
This query hunts for inbound emails that contain URLs embedded in QR codes and originate from senders that are not commonly observed in the environment, a common technique used in QR-based phishing campaigns.
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Andre Zeemering@Azeemering
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Detections.ai Community
9 months ago
141231
This rule detects Microsoft Teams chat or call activity initiated by external users whose domains are not present in a pre-defined whitelist. It specifically looks for 'ChatCreated' or 'CallParticipantDetail' actions from external users and filters out activity from known, whitelisted external domains. This can help identify potentially unauthorized or suspicious external communication within Microsoft Teams.
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Rudra Verma@Rudraverma
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CyberHawk Consultancy
9 months ago
3077
This query parses the complex JSON parameters of the New-TransportRule and Set-TransportRule commands to find instances where email is being secretly copied externally or security is being lowered.
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Daniel Miller@dxmiller
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Detections.ai Community
9 months ago
170128
This query uses the Machine Learning series_decompose_anomalies function to build a baseline of "normal" transport rule modification behavior. If your organization typically changes 0 rules a week, and suddenly 5 are changed at 2 AM on a Saturday, this query will catch it regardless of what the parameters are.
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Daniel Miller@dxmiller
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Detections.ai Community
9 months ago
10083
This rule detects chat or call activity by external users in Microsoft Teams whose source tenant is not present in a pre-defined whitelist. This could indicate unauthorized external communication or potential data exfiltration attempts.
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Rudra Verma@Rudraverma
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CyberHawk Consultancy
9 months ago
171106
This KQL check for email links that were clicked/ email attachment that were opened before recall
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Udi B@Udi
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Detections.ai Community
9 months ago
352257
Detects emails containing threat-actor lure links to trojanized ScreenConnect MSI files, specifically targeting 'cld.pt' downloads with 'COMPROBANTE*.msi' patterns. The rule also looks for 'COMPROBANTE' keywords in email subjects as a fallback.
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Daniel Jeremiah@daniyyell
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Detections.ai Community
9 months ago
284278
This rule detects instances where a SharePoint or OneDrive file/folder is shared with a guest user whose email address is identified as a threat intelligence indicator. This could indicate an attempt to exfiltrate data to a known malicious entity or an account compromise being used for data staging.
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Bartosz Turek@turekbar
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Detections.ai Community
9 months ago
190118
This rule tracks and deduplicates alert emails from a Managed Security Service Provider (MSSP). It identifies emails from a specific sender, filters by subject keywords (e.g., severity levels), and groups them into sessions to prevent duplicate alerts. It also extracts case numbers from portal URLs found within the emails.
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Nicholas Isakson@nisakson2000
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Detections.ai Community
9 months ago
5059
This rule detects suspicious activity related to mailbox access within Office 365. It has two main parts: 1) Identifies users accessing a high number of unique mailboxes belonging to other users. 2) Identifies users accessing a high number of unique folders within another user's mailbox. Both scenarios can indicate unauthorized access, data exfiltration attempts, or compromised accounts.
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Mehulkumar Savajani@Msavajani
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Detections.ai Community
9 months ago
476404
This rule detects when a user from a specified watchlist sends an email with a large attachment (over 5MB).
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Sakshyam Sambyal@Sakshyam
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Detections.ai Community
9 months ago
7069
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