Detections

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

404 detections

This rule detects suspicious ad click traffic that routes through Google Ad Services It specifically looks for URLs containing Google Click Identifier (gclid), an ad URL, and a placement ID, while excluding legitimate ad routing services. This could indicate ad fraud or malvertising.
Most but not all clicks on Google ads are routed this way.
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Salten Fisk@saltenfisk
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Detections.ai Community
1 year ago
8272
The analytic identifies the execution of the native mimikatz.exe binary on Windows systems, including instances where the binary is renamed. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and original file names. This activity is significant because Mimikatz is a widely used tool for extracting authentication credentials, posing a severe security risk. If confirmed malicious, this activity could allow attackers to obtain sensitive credentials, escalate privileges, and move laterally within the network, leading to potential data breaches and system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0055
Detects the download of a Java Archive (.jar) file from common file-sharing services like Dropbox or MediaFire. This behavior is associated with sophisticated email campaigns where attackers use PDF attachments with embedded links to trick users into downloading and executing Remote Access Trojans (RATs).
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Robert Fly@robertfly
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Detections.ai Community
1 year ago
0065
This rule detects potential proxy bypass attempts by identifying network connections on common web ports (80, 443) that are allowed by the network firewall but do not appear in the proxy logs. It correlates network traffic from the Network_Traffic data model with proxy traffic from the Web data model. The rule specifically filters for external-bound traffic by excluding private and multicast IP addresses.
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Anoozilla HunterX@AnoozillaHunterX
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Detections.ai Community
1 year ago
2049
Detects network connections to domains matching patterns commonly used by the Scattered Spider threat group for phishing campaigns.
The group often registers domains that mimic legitimate corporate services by appending suffixes like "-sso", "-servicedesk", "-okta", "-vpn", or "-helpdesk" to a target's name (e.g., victim-sso.com).
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Aaron Mog@AaronMogS2S
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Detections.ai Community
1 year ago
3279
'This rule identifies a web request with a user agent header known to belong PowerShell. <br>You can add custom Powershell indicating User-Agent headers using a watchlist, for more information refer to the [UnusualUserAgents Watchlist](https://aka.ms/ASimUnusualUserAgentsWatchlist).<br><br>
This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1096
'Identifies callouts to Discord CDN addresses for risky file extensions. This detection will trigger when a callout for a risky file is made to a discord server that has only been seen once in your environment.
Unique discord servers are identified using the server ID that is included in the request URL (DiscordServerId in query). Discord CDN has been used in multiple campaigns to download additional payloads.
This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0066
The analytic detects outbound SMB (Server Message Block) connections from internal hosts to external servers. It identifies this activity by monitoring network traffic for SMB requests directed towards the Internet, which are unusual for standard operations. This detection is significant for a SOC as it can indicate an attacker's attempt to retrieve credential hashes through compromised servers, a key step in lateral movement and privilege escalation. If confirmed malicious, this activity could lead to unauthorized access to sensitive data and potential full system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5082
'This rule identifies a web request with a user agent header known to belong to a hacking tool. This indicates a hacking tool is used on the host.<br>You can add custom hacking tool indicating User-Agent headers using a watchlist, for more information refer to the [UnusualUserAgents Watchlist](https://aka.ms/ASimUnusualUserAgentsWatchlist).
This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1059
'This rule identifies a web request to a URL that holds a file type, including .ps1, .bat, .vbs, and .scr that can be harmful if downloaded. This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2052
'This rule identifies communication with hosts that have a domain name that might have been generated by a Domain Generation Algorithm (DGA).
DGAs are used by malware to generate rendezvous points that are difficult to predict in advance. This detection uses the top 1 million domain names to build a model of what normal domains look like nad uses the model to identify domains that may have been randomly generated by an algorithm. You can modify the triThreshold and dgaLengthThreshold query parameters to change Analytic Rule sensitivity. The higher the numbers, the less noisy the rule is.
This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0050
This rule identifies a source that repeatedly fails to authenticate to a web service (HTTP response code 403). This may indicate a [brute force](https://en.wikipedia.org/wiki/Brute-force_attack) or [credential stuffing](https://en.wikipedia.org/wiki/Credential_stuffing) attack.
This rule uses the [Advanced Security Information Model (ASIM)](https://aka.ms/AboutSIM) and supports any web session source that complies with ASIM.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0045
'This detection will identify network requests in HTTP proxy data that contains Base64 encoded IP addresses. After identifying candidates the query joins with DeviceNetworkEvents to idnetify any machine within the network using that IP address. Alerts indicate that the IP address of a machine within your network was seen with it's IP address base64 encoded in an outbound web request. This method of egressing the IP was seen used in POLONIUM's RunningRAT tool, however the detection is generic.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1045
'This detection will identify network requests in HTTP proxy data that contains Base64 encoded usernames from machines in the DeviceEvents table.
This technique was seen usee by POLONIUM in their RunningRAT tool.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0033
'This composite hunting query will highlight any HTTP traffic in CommonSecurityLog web proxies (such as ZScaler) that match known patterns used by red teaming tools potentially stolen from FireEye. Most FireEye red teaming tools are designed to mimic
legitimate API activity, false positives are common. This query includes a basic check to determine how common a hostname is in you environment, and allows you to modify this threshold to remove legitimate traffic from the query results.
This query contains only a subset of potential FireEye red team tool communications, and therefore should not be relied upon alone :) .'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
'This rule identifies a web request with a user agent header known to belong to a crypto miner. This indicates a crypto miner may have infected the client machine.<br>You can add custom crypto mining indicating User-Agent headers using a watchlist, for more information refer to the [UnusualUserAgents Watchlist](https://aka.ms/ASimUnusualUserAgentsWatchlist).<br><br> This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM WebSession schema (ASIM WebSession Schema)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0024
'Query finds accounts recorded as disabled by AD in previous time period but still using proxy in current time period. Presumes default squid log format is used. http://www.squid-cache.org/Doc/config/access_log/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0021
'Detects first connection to an unpopular website (possible malicious payload delivery).'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0020
This analytic detects suspicious modifications to Unix shell configuration files, such as `.bashrc` or `.profile`, which may indicate an attempt to alter system behavior or gain unauthorized access. Unauthorized changes to these files can be used to execute malicious commands, escalate privileges, or hide malicious activities. By monitoring for unusual or unauthorized modifications to shell configuration files, this analytic helps identify potential security threats, allowing security teams to respond quickly and mitigate risks.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
4088
The following analytic detects attempts to stop a service on Linux systems. It leverages data from Linux Auditd. This activity is significant as adversaries often stop or terminate security or critical services to disable defenses or disrupt operations, as seen in malware like Industroyer2. If confirmed malicious, this could lead to the disabling of security mechanisms, allowing attackers to persist, escalate privileges, or deploy destructive payloads, severely impacting system integrity and availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0054
Detects a specific user agent string and host ('api.dropbox.com') associated with an APT40 Dropbox tool, indicating potential data exfiltration or command and control activity via Dropbox.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0054
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