Detections

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

3,141 detections

This rule detects inbound email messages containing HTML or related file types (htm, mhtml, shtml) that passed all standard authentication checks (SPF, DKIM, DMARC). This combination is often indicative of malicious phishing campaigns (such as those using LinXcoded or Mirage2FA techniques) sent from compromised, yet properly authenticated, Microsoft 365 or similar cloud-hosted email accounts, which bypass traditional sender reputation filters.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
102
Detects phishing emails purportedly from Docusign that contain malicious links which redirect users through legitimate identity provider domains (e.g., login.microsoftonline.com, accounts.google.com) before landing on non-trusted infrastructure. This redirect-chain pattern is indicative of NovaCookies Adversary-in-the-Middle (AiTM) delivery, used to facilitate credential or session cookie theft.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
102
Detects phishing emails purportedly from Docusign that contain malicious links which redirect users through legitimate identity provider domains (e.g., login.microsoftonline.com, accounts.google.com) before landing on non-trusted infrastructure. This redirect-chain pattern is indicative of NovaCookies Adversary-in-the-Middle (AiTM) delivery, used to facilitate credential or session cookie theft.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
102
Detects phishing attempts leveraging SendGrid infrastructure to send emails that impersonate well-known financial brands. The detection looks for emails with authentication checks passing (SPF/DKIM/DMARC) where the sender domain is suspicious (e.g., .asia or .com not matching the brand) and the volume of such messages suggests an automated campaign.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
102
Detects incoming emails that use 'Apple' or 'Find My' related strings in the sender display name while originating from common consumer email relay domains like Gmail or iCloud, which is indicative of a social engineering or phishing attempt attempting to impersonate Apple support.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects phishing messages that deliberately mix writing systems/scripts/homoglyphs in the Subject line as ONE corroborating signal within a broader, multi-signal phishing pattern. Hardened against false positives: brand/product tokens (e.g. Microsoft, PayPal) are stripped before the Latin-script check so a lone brand mention in non-Latin correspondence doesn't count as mixed-script; the suspicious-URL signal requires a high-confidence credential/urgency term (not generic business vocabulary); sender risk requires the domain to be new to both the recipient and the organization; and at least three independent signal categories (not two) must corroborate the language-confusion signal before the rule fires.
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Arnold Chan@slaz
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Detection & Hunting Community
1 month ago
001
Detects a sequence of events where a user performs a device-code authentication followed rapidly by a device enrollment, and subsequently continues to access cloud services (Microsoft Graph, Exchange Online, Intune) shortly after their account password has been reset. This pattern is indicative of persistent access maintained via a registered device or OAuth token that survives credential remediation.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
102
Detects high-risk administrative actions in Microsoft 365, such as new MFA method registration, OAuth app consent grants, or email forwarding rule creation, occurring in sessions that lack fresh authentication (often indicative of a session-cookie replay attack).
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects Microsoft 365 sign-in events where MFA was successfully satisfied, but the sign-in is simultaneously flagged by risk detection engines as exhibiting anomalous token or session characteristics, indicative of Adversary-in-the-Middle (AiTM) session hijacking.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
This rule detects DNS lookups, email URL clicks, and network connections involving lookalike domains that mimic Singaporean government or infrastructure services (e.g., LTA, OneMotoring, ERP, Gov.sg). It employs a regex-based pattern match for common brand-keywords combined with high-risk top-level domains, identifying potential phishing activity associated with the JWR framework that utilizes algorithmically varied, single-suffix rotated lookalike domains.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects anomalous sign-in attempts to the OfficeHome application that result in OAuth error 90014 (frequently associated with application access issues or invalid consent) combined with an implausible mismatch between the reported Windows 10 operating system and mobile-specific browser user agents (e.g., Mobile Safari, Chrome Mobile). This behavior may indicate an adversary attempting to mimic legitimate device traffic to bypass conditional access policies or facilitate OAuth-based token manipulation.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects session hijacking (AiTM) attempts where a failed or interrupted sign-in (ResultType 50199) is followed by a successful login using the same SessionId but with an Axios user-agent, indicating automated replay of a stolen session token rather than legitimate browser usage.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects a suspicious spike in MailItemsAccessed operations occurring across multiple distinct tenant organization IDs within a 60-second window, using the same ClientAppId. This behavior is indicative of automated, centralized credential abuse or mailbox collection tools (often associated with campaigns like Storm-2755) rather than legitimate, isolated user or service-level activity.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
002
Detects anomalous Microsoft Graph API activity characterized by user enumeration or querying for sensitive organizational groups (e.g., payroll, finance, HR) often associated with post-AiTM account-takeover reconnaissance. This detection specifically identifies multiple requests for sensitive URIs or high-count enumeration requests originating from suspicious User-Agent strings like 'axios/1.18.1', commonly observed in threat actor activity such as Storm-2755.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
402
Detects potentially malicious OAuth device code sign-ins by identifying sign-in events that exhibit anomalous characteristics, such as atypical geographic locations, rare client-application combinations, unmanaged/noncompliant device status, or elevated risk signals associated with the account. This detection helps identify account compromise or malicious OAuth consent activity often associated with 'EvilTokens' or device-code phishing attacks.
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Arnold Chan@slaz
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Hunters
1 month ago
102
Detects potentially malicious OAuth device code sign-ins by identifying sign-in events that exhibit anomalous characteristics, such as atypical geographic locations, rare client-application combinations, unmanaged/noncompliant device status, or elevated risk signals associated with the account. This detection helps identify account compromise or malicious OAuth consent activity often associated with 'EvilTokens' or device-code phishing attacks.
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Arnold Chan@slaz
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Detection & Hunting Community
1 month ago
102
Detects an administrator account rapidly granting mailbox permissions (Add-MailboxPermission, Add-RecipientPermission, Set-MailboxFolderPermission) to a large number of objects within a short timeframe (15 minutes). The rule correlates this activity with a prior 'risky' sign-in or a sign-in using device-code flow, indicative of potential EvilToken or similar adversary-in-the-middle proxy-based session hijacking.
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Arnold Chan@slaz
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Detections.ai Community
1 month ago
102
Detects high-volume deletion or recycling of files within OneDrive or SharePoint for a specific user, which may indicate malicious activity such as data destruction, ransomware, or unauthorized data exfiltration staging.
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Arnold Chan@slaz
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Midnight Slayer
1 month ago
4014
This rule hunts for indicators associated with the TrustSink technique, which involves using rogue External Authentication Methods (EAM) or malicious OIDC providers to bypass authentication or maintain persistence within a cloud environment. It monitors Azure AD sign-in and audit logs, alongside DNS and network events, for references to known malicious domains and URLs used for EAM-based attacks.
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Arnold Chan@slaz
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Hunters
1 month ago
102
This rule hunts for indicators associated with the TrustSink technique, which involves using rogue External Authentication Methods (EAM) or malicious OIDC providers to bypass authentication or maintain persistence within a cloud environment. It monitors Azure AD sign-in and audit logs, alongside DNS and network events, for references to known malicious domains and URLs used for EAM-based attacks.
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Arnold Chan@slaz
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Midnight Slayer
1 month ago
102
Detects inbound email messages containing keywords and phrases consistent with extortion attempts, specifically referencing stolen data, unauthorized access, and demands for cryptocurrency payment.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
108
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