Detections

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

6,208 detections

This rule detects the execution of 'nimgrab.exe', a tool associated with the Nim programming framework, which is often used for downloading files. Detection is based on the process name 'nimgrab.exe' or specific file hashes (MD5, SHA256, Imphash) associated with known nimgrab binaries. This tool can be abused by adversaries for ingress tool transfer.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0031
Detects suspicious usage of `curl.exe` on Windows to download files into common temporary or user-controlled directories. This rule specifically looks for `curl.exe` being executed and writing its output to locations like `%appdata%`, `%public%`, `%temp%`, user desktop, or common temporary system directories, often associated with malware staging or persistence. It also identifies downloads of specific file extensions commonly used for malicious payloads.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0031
Detects the execution of certutil.exe with specific flags ('urlcache' or 'verifyctl') to download files from known file-sharing or content delivery network (CDN) websites. This technique is often used by adversaries for ingress tool transfer or to retrieve malicious payloads.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0030
Detects the execution of `certutil.exe` with specific command-line arguments (`urlcache` or `verifyctl`) combined with an HTTP URL, indicating an attempt to download files using this utility. This technique is often used by adversaries for ingress tool transfer or to retrieve malicious payloads.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0027
Find web Traffic going to port 80 or 443
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0022
This rule detects the execution or creation of files identified as Remote Access Tools (RATs) based on a Google Cloud Threat Intelligence (GCTI) feed. It correlates process launch, module load, or file creation events with known SHA256 hashes of RATs provided by the GCTI feed. The rule specifically looks for events where the SHA256 hash of the process or file matches a hash from the 'Remote Access Tools' threat feed within the GCTI graph.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
2073
An adversary may use legitimate desktop support and remote access software, such as Team Viewer, Go2Assist, LogMein, AmmyyAdmin, etc, to establish an interactive command and control channel to target systems within networks.
These services are commonly used as legitimate technical support software, and may be allowed by application control within a target environment.
Remote access tools like VNC, Ammyy, and Teamviewer are used frequently when compared with other legitimate software commonly used by adversaries. (Citation: Symantec Living off the Land)
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
003
This analytic identifies outbound LDAP traffic to external IP addresses. It leverages network traffic data to detect connections on ports 389 (LDAP) or 636 (LDAPS) that are not directed to private IP ranges (RFC1918). This activity is significant because outbound LDAP traffic can indicate potential data exfiltration or unauthorized access attempts. If confirmed malicious, attackers could exploit this to access sensitive directory information, leading to data breaches or further network compromise. The rule specifically excludes traffic between internal source and destination IPs.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5071
This rule detects when a file, identified as malicious by Google Safe Browsing, initiates an outbound network connection to an IP address known to be a Tor Exit Node, as identified by Google Cloud Threat Intelligence (GCTI) Feed. This indicates potential command and control (C2) communication or data exfiltration by malware attempting to anonymize its network traffic.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0063
This rule detects outbound network connections to IP addresses that have been observed for the first time within the last 24 hours. It specifically excludes connections to private IP address ranges (RFC1918). The detection relies on correlating current network connection events with historical 'first seen' data for IP addresses from an entity graph.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
1061
Detects suspicious attempts to download files from legitimate Microsoft domains (Outlook and OneNote) using command-line tools or PowerShell. Adversaries may leverage these trusted domains to host malicious files, bypassing traditional perimeter defenses and making the activity appear legitimate. The rule specifically looks for common download utilities like curl, wget, Invoke-WebRequest, and Start-BitsTransfer in conjunction with specific Microsoft attachment/sync domains.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
3030
The following analytic identifies network traffic where the higher layer protocol does not match the expected port, such as non-HTTP traffic on TCP port 80. It leverages data from network traffic inspection technologies like Bro or Palo Alto Networks firewalls. This activity is significant because it may indicate attempts to bypass firewall restrictions or conceal malicious communications. If confirmed malicious, this behavior could allow attackers to evade detection, maintain persistence, or exfiltrate data through commonly allowed ports, posing a significant threat to network security.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
2059
This rule detects outbound network connections to known Tor exit nodes. It leverages a Google Cloud Threat Intelligence (GCTI) feed that provides a list of current Tor exit node IP addresses. The rule specifically looks for allowed network connections where the target IP address is identified as a Tor exit node by the GCTI feed. This can indicate an attempt to anonymize network traffic, which is often associated with malicious activity.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
1050
The following analytic identifies the use of cleartext protocols that risk leaking sensitive information. It detects network traffic on legacy protocols such as Telnet (port 23), POP3 (port 110), IMAP (port 143), and non-anonymous FTP (port 21). The detection leverages the Network_Traffic data model to identify TCP traffic on these ports. Monitoring this activity is crucial as it can expose credentials and other sensitive data to interception. If confirmed malicious, attackers could capture authentication details, leading to unauthorized access and potential data breaches.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1055
Finds PowerShell execution events that could involve a download.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0012
Detects DNS queries initiated by "QuickAssist.exe" to the Microsoft Quick Assist primary endpoint. This activity is often associated with social engineering attacks leading to ransomware, where threat actors misuse Quick Assist to gain remote access to a victim's system.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0026
This rule detects when a file is downloaded via HTTP and subsequently created on a system, where the file's SHA256 hash and the URL it was downloaded from are identified as malicious through VirusTotal relationships. It correlates HTTP network events with file creation events, ensuring the download precedes the file creation, and then enriches this information with VirusTotal data to confirm the malicious nature of the file and its source URL.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
1046
This rule detects the use of the `netsh interface portproxy` command to enable port forwarding, specifically looking for `v4tov4` configurations. It also identifies the creation or modification of associated registry settings under `HKLM\System\CurrentControlSet\Services\PortProxy\v4tov4`, which are indicative of port proxying being configured on a Windows system.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
1 year ago
0045
Check to see if Smart screen is working. This can also be used to track users going to websites.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0011
Detects AnyDesk writing binary files to disk other than "gcapi.dll".
According to RedCanary research it is highly abnormal for AnyDesk to write executable files to disk besides gcapi.dll,
which is a legitimate DLL that is part of the Google Chrome web browser used to interact with the Google Cloud API. (See reference section for more details)
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
002
Detects potential RDP connection via Mstsc using a local ".rdp" file
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
002
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