Detections

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

983 detections

This rule detects successful Azure AD authentication attempts originating from known hosting provider or VPS IP addresses, combined with anomalous behavior such as headless browser user agents, impossible travel, or high-risk sign-in flags. This pattern is indicative of Adversary-in-the-Middle (AiTM) phishing proxies like Evilginx or Bluekit, which attempt to bypass MFA by proxying the authentication process.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
005
Detects successful authentication events from accounts identified as service, managed, or robot accounts (e.g., svc_, sa_, msol, robot) originating from external IP addresses or exhibiting an unusually high number of distinct source IP addresses. This behavior is indicative of potential credential theft, token replay attacks, or unauthorized usage of service account identities.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
003
Detects successful authentication to Atlassian Jira from an anomalous network source (e.g., proxied or unusual geolocation/ASN) following a period of credential inactivity. This activity is consistent with tactics used by the HellCat ransomware group, who leverage credentials harvested by infostealers (such as Raccoon, Redline, StealC, or Lumma) to gain initial unauthorized access to corporate Jira environments.
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Duo Tech@duotech
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Detections.ai Community
4 months ago
001
This rule monitors for successful external logins occurring on an endpoint that previously demonstrated patterns of suspected MFA fatigue (multiple failed push notifications) and subsequent internal reconnaissance activity (execution of commands used for domain or system discovery). The rule correlates these events to identify potential compromised credentials being actively used for lateral movement or persistence.
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Ankit Mehta@Secvyn
Bharat Cyber Guardians
4 months ago
004
Detects evidence of common Impacket tool execution (e.g., psexec, wmiexec, smbexec, ntlmrelayx), unauthorized access to sensitive SMB administrative shares (ADMIN$, IPC$), creation of suspicious services often used for remote execution, and lateral movement via NTLM network logons.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
004
Detects successful or failed logon attempts originating from IP addresses identified as associated with botnets, C2 infrastructure, or proxies by threat intelligence feeds. This indicates potential malicious activity or compromised accounts.
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nomit vyas@xoxo
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Detections.ai Community
4 months ago
206
This rule detects successful SSH login events utilizing public key authentication for the 'vmanage-admin' user. It aggregates login events by source IP, username, and host to identify patterns of access for this specific administrative account.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
004
Detects unauthorized changes to sensitive payroll information (such as bank accounts or direct deposit details) or suspicious inbox rule creations within Microsoft 365 or HR SaaS environments that occur immediately following anomalous authentication activity. The rule targets indicators of AiTM (Adversary-in-the-Middle) session hijacking, such as unusual user agents, unmanaged device usage, or potential token reuse.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
001
Detects privilege escalation events (assigning special privileges or executing privileged operations) occurring on a host shortly after the execution of legitimate remote support tools such as Quick Assist or msra.exe. This pattern is consistent with social engineering campaigns where attackers gain remote access via support tools and then perform local privilege escalation.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
005
Detects high-frequency failed logon attempts (Event ID 4625) from a single IP address within a short time window, indicating potential brute force or password spraying activity targeting Windows systems.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
001
Detects Kerberos service ticket requests (TGS) where the encryption type is set to 0x17 (RC4-HMAC). This is commonly used in Kerberoasting attacks to capture service ticket hashes for offline brute-force attacks.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
001
Detects successful NTLMv1 logon events (Event ID 4624) where the logon type is 3 (Network). NTLMv1 is a legacy and insecure authentication protocol. Its use in a modern environment, particularly for network logons, is often associated with pass-the-hash attacks or legacy compatibility issues that attackers may exploit.
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Ankit Mehta@Secvyn
Bharat Cyber Guardians
4 months ago
001
Detects successful NTLMv1 logon events (Event ID 4624) where the logon type is 3 (Network). NTLMv1 is a legacy and insecure authentication protocol. Its use in a modern environment, particularly for network logons, is often associated with pass-the-hash attacks or legacy compatibility issues that attackers may exploit.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
201
Detects potential Pass-the-Hash lateral movement where a single account uses NTLM authentication as a local administrator to access three or more distinct devices within a 30-minute window, a pattern often indicative of automated credential propagation.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
101
Detects potential Adversary-in-the-Middle (AiTM) phishing activity by identifying successful user sign-ins from a new, historically unseen IP address occurring within 30 minutes of a legitimate sign-in from a known IP, indicating the potential replay of a stolen session or refresh token.
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Ankit Mehta@Secvyn
Bharat Cyber Guardians
4 months ago
103
This rule detects successful sign-ins using OAuth from residential IP addresses. It joins `SigninLogs` with `IdentityLogonEvents` to correlate successful OAuth authentications with user logon events. The intent is to identify potentially suspicious access, possibly indicating credential abuse or unauthorized access attempts from non-corporate or unexpected locations.
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Ankit Mehta@Secvyn
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Detections.ai Community
4 months ago
15050
Identifies an interactive logon session established from a RedVDS IP executing PowerShell downloaders to pull secondary payloads. This rule correlates process execution events for PowerShell with specific command-line patterns indicative of downloading content (Net.WebClient or DownloadString) with interactive logon events originating from a known RedVDS IP address.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
109
This rule detects suspicious activity on high blast radius accounts, specifically correlating failed authentication attempts, password resets, and successful logons outside business hours.

The rule prioritizes detection based on a password reset event to produce an informational severity alert, then looks for preceding failed authentications and subsequent out-of-hours logons to indicate a potential compromise by raising severity accordingly.

You will need to utilise the AlertSeverityOverride configuration, pointed at the AlertSeverity field, in your Sentinel rule metaconfig to use this detection effectively.

Hard requirement: Need UEBA enabled in your tenant to populate the BlastRadius field in your IdentityInfo table.

Change each stage to suit your log source for the behaviour mapped to this stage.

Add in other stages if needed to add more dynamic severity (e.g., Account has high blast radius AND is a GA AND was logged in to from outside of expected geolocation > Critical severity)
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Christopher Scott@Scocha
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Detections.ai Community
4 months ago
12115
Detects anomalous activities associated with the Zerologon (CVE-2020-1472) vulnerability. The rule identifies suspicious machine account password changes, NTLM authentication from potentially untrusted subnets or unconfigured workstations, and privilege escalation indicators occurring on domain controllers.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
003
This rule detects successful network logons (LogonType 3) using NTLM (NTLMv1 or NTLMv2) where the authentication results in an elevated token and the logon originates from a different workstation than the target computer. This combination of factors can indicate lateral movement attempts, especially when an adversary has obtained NTLM hashes (e.g., via Pass-the-Hash or NTLM relay attacks) and is attempting to authenticate to other systems on the network. The rule excludes machine accounts and anonymous logons, as well as loopback authentications, to reduce noise.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
004
This rule correlates three distinct events to detect a potential credential theft and lateral movement chain: an LSASS credential dump, followed by an NTLM network logon, and then a DCOM activation of mmc.exe with the '-Embedding' flag on the target system. This sequence of events is indicative of an attacker compromising credentials, using them to move laterally, and then potentially executing further commands or tools via DCOM.
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Ibrahim Saud@tektrix
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Detections.ai Community
4 months ago
004
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