Detections

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

227 detections

Detects potential unauthorized browser extension installations or debugging activities by monitoring process and network events related to popular web browsers.
avatar
Ankit Mehta@Secvyn
avatar
Detections.ai Community
1 year ago
70225
Detects when a web browser (Chrome, Edge, Firefox, Brave, Opera) initiates a process that is not another instance of itself. This could indicate a drive-by download, execution of malicious code, or other suspicious activity originating from a browser.
avatar
Ankit Mehta@Secvyn
avatar
Detections.ai Community
1 year ago
60182
Detects attempts to read the memory of browser processes (Chrome, Edge, Firefox, Brave, Opera). This activity can be indicative of credential dumping or other forms of data exfiltration from web browsers.
avatar
Ankit Mehta@Secvyn
avatar
Detections.ai Community
1 year ago
30161
This rule detects the presence of known Chaos ransomware samples by matching their SHA256 hashes against process execution events and file events. If a process with a matching hash is executed or a file with a matching hash is observed, an alert will be triggered.
avatar
Ankit Mehta@Secvyn
avatar
Detections.ai Community
1 year ago
10153
Detects modifications to the 'SSLKEYLOGFILE' environment variable in the Windows Registry. This variable is often used by applications like web browsers to log SSL/TLS session keys to a file, which can then be used to decrypt encrypted network traffic. Malicious actors might enable this to capture sensitive data.
avatar
Ankit Mehta@Secvyn
avatar
Detections.ai Community
1 year ago
1052
This analytic detects the configuration of TFTP services on Cisco IOS devices that could be used to exfiltrate sensitive configuration files. Threat actors like Static Tundra have been observed configuring TFTP servers to make device configuration files accessible for exfiltration after gaining initial access. The detection specifically looks for commands that expose critical configuration files such as startup-config, running-config, and other sensitive system information through TFTP. This activity is particularly concerning as it may represent an attempt to steal credentials, network topology information, and other sensitive data stored in device configurations.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
1059
The analytic detects when a Windows RDP client attempts to execute an RDP file from a temporary directory, downloads directory, or Outlook directories. This detection is significant as it can indicate an attempt for an adversary to deliver a .rdp file, which may be leveraged by attackers to control or exfiltrate data. If confirmed malicious, this activity could lead to unauthorized access, data theft, or further lateral movement within the network.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0059
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
avatar
Splunk Security Content
1 year ago
0055
'Detects potentially malicious Visual Studio Code (VSCode) extensions installed on a users system, which threat actors might use to control devices and exfiltrate personal information.
Ref: https://blog.checkpoint.com/securing-the-cloud/malicious-vscode-extensions-with-more-than-45k-downloads-steal-pii-and-enable-backdoors/'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
20132
Looks for suspicious base64 encoded registry keys being created.
Author: Jouni Mikkola
References:
https://threathunt.blog/registry-hunts/
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
3161
Goal: Find machines in the last N days where the SystemGuardSecurityLevel value NOW is less than it was BEFORE.
Step 1: Get a list of all security levels in the system where the level is not null.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
6056
This query will provide a report of many of the best practice configurations for Defender ATP deployment. Special Thanks to Gilad Mittelman for the initial inspiration and concept.
Any tests which are reporting "BAD" as a result imply that the associated capability is not configured per best practice recommendation.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
4046
Find use of Alternate Data Streams (ADS) for anti-forensic purposes.
Alternate Data Streams execution.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2044
Original Sigma Rule: https://github.com/Neo23x0/sigma/blob/master/rules/windows/process_creation/win_susp_schtask_creation.yml.
Questions via Twitter: @janvonkirchheim.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2044
This query was originally published in the threat analytics report, Ransomware continues to hit healthcare, critical services. There is also a related blog.
In April of 2020, security researchers observed multiple ransomware campaigns using the same set of techniques.
The following query detects attempts to use fsutil.exe to clear system logs and delete forensic artifacts.
The See also section below lists more queries related to techniques shared by these campaigns.
Reference - https://www.microsoft.com/security/blog/2020/04/28/ransomware-groups-continue-to-target-healthcare-critical-services-heres-how-to-reduce-risk/
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0044
This query finds a software by name and/or version
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2041
"This query searches for any files in Cloud App Events that have trigger a security alert."
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
1041
This query was originally published in the threat analytics report, Exploitation of CVE-2019-0708 (BlueKeep).
CVE-2019-0708, also known as BlueKeep, is a critical remote code execution vulnerability involving RDP. Soon after its disclosure, the NSA issued a rare advisory about this vulnerability, out of concern that it could be used to quickly spread malware. Attackers have since used this vulnerability to install cryptocurrency miners on targets.
Microsoft has issued updates for this vulnerability, as well as guidance for protecting operating systems that we no longer support. Microsoft Defender ATP also contains behavioral detections for defending against this threat.
The following query locates Windows 7 or Windows Server 2008 machines initiating outbound connections to internal or public IP addresses on TCP port 3389. It filters out common RDP programs and scanning tools and shows the number of connections per machine. It can identify machines with relatively intense outbound network activity on the common RDP port (TCP/3389). You can use it to find processes that might be scanning for possible targets or exhibiting worm-like behavior.
References:
https://nvd.nist.gov/vuln/detail/CVE-2019-0708
https://www.nsa.gov/News-Features/News-Stories/Article-View/Article/1865726/nsa-cybersecurity-advisory-patch-remote-desktop-services-on-legacy-versions-of/
https://www.wired.com/story/bluekeep-hacking-cryptocurrency-mining/
https://portal.msrc.microsoft.com/security-guidance/advisory/CVE-2019-0708
https://support.microsoft.com/help/4500705/customer-guidance-for-cve-2019-0708
https://www.microsoft.com/security/blog/2019/11/07/the-new-cve-2019-0708-rdp-exploit-attacks-explained/
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2039
This query was originally published in the threat analytics report, ironSource PUA & unwanted apps impact millions.
IronSource provides software bundling tools for many popular legitimate apps, such as FileZilla. However, some of ironSource's bundling tools are considered PUA, because they exhibit potentially unwanted behavior. One component of these tools, detected by Microsoft as Prifou, silently transmits system information from the user. It also installs an outdated version of Chromium browser with various browser extensions, resets the user's home page, changes their search engine settings, and forces Chromium and itself to launch at startup.
The following query can be used to locate unique command-line strings used by ironSource bundlers to launch Prifou, as well as commands used by Prifou to install Chromium.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
1036
Non-local logons with the built-in administrator (-500) account.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2032
This query was originally published in the threat analytics report, Ransomware continues to hit healthcare, critical services. There is also a related blog.
In April of 2020, security researchers observed multiple ransomware campaigns using the same set of techniques.
The following query detects suspicious use of Alternate Data Streams (ADS), which may indicate an attempt to mask malicious activity. These campaigns have been known to deploy ransomware in-memory and exploit ADS.
The See also section below lists more queries related to techniques shared by these campaigns.
References:
https://www.microsoft.com/security/blog/2020/04/28/ransomware-groups-continue-to-target-healthcare-critical-services-heres-how-to-reduce-risk/
https://docs.microsoft.com/sysinternals/downloads/streams
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2032
Page 5 of 11