Detections

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

6,203 detections

'Threat actors may use tools such as Curl to download additional files, communicate with C2 infrastructure, or exfiltrate data. This query looks for new files being downloaded using Curl. Curl also has legitimate uses files and hosts should be reviewed to identify potentially malicious activity.
Ref: https://www.microsoft.com/security/blog/2022/07/27/untangling-knotweed-european-private-sector-offensive-actor-using-0-day-exploits/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
'This hunting query looks for new Service Principals running queries that have not previously been seen running queries.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2029
Detects setting a custom URL for OneDriveStandaloneUpdater.exe to download a file from the Internet without executing any
anomalous executables with suspicious arguments. The downloaded file will be in C:\Users\redacted\AppData\Local\Microsoft\OneDrive\StandaloneUpdaterreSignInSettingsConfig.json
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
005
'This hunting query will identify instances where a single user account has seen a high incidence of failed attempts from highly volatile IP addresses
Changing IP address for every password attempt is becoming a more common technique amongst sophisticated threat groups. Often threat groups will randomise
the user agent they are using as well as IP address. This technique has been enabled by the emergence of services providing huge numbers of residential IP
addresses. These services are often enabled through malicious browser plugins. This query is best executed over longer timeframes.
Reduce the timeRange if you have too much data. Results with the highest "IPs", "Failures" and "DaysWithAttempts" are good candidates for further
investigation. This query intentionally does not cluster on UserAgent, IP etc. This query is clustering on the highly volatile IP behaviour.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2029
Detects the execution of well known tools that can be abused for data exfiltration and tunneling.
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
005
'Identifies the host and account that executed AdFind by hash and filename in addition to common and unique flags that are used by many threat actors in discovery.
To use this analytics rule, make sure you have deployed the [ASIM normalization parsers](https://aka.ms/ASimProcessEvent)'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1029
Detects the presence and execution of Inveigh via dropped artefacts
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
005
Detects the creation of log files during a TeamViewer remote session
Yamato Security Hayabusa@YamatoSecurityHayabusa
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Yamato Security Hayabusa Rules
1 year ago
005
'Detects a URL being added to an application where the domain is not one that is associated with the tenant.
The query uses domains seen in sign in logs to determine if the domain is associated with the tenant.
Applications associated with URLs not controlled by the organization can pose a security risk.
Ref: https://learn.microsoft.com/en-gb/entra/architecture/security-operations-applications#application-configuration-changes'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
'This query dynamically identifies Exchange servers and then looks for instances where the IIS worker process initiates a call out to a remote URL using either cmd.exe or powershell.exe.
This behaviour was described as post-compromise behaviour following exploitation of CVE-2022-41040 and CVE-2022-41082, this pattern of activity was use to download additional tools to the server. This suspicious activity is generic.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
StrRAT is a Java-based remote access tool which steals browser credentials, logs keystrokes and take remote control of infected systems. It also has a module to download additional payload onto to the infected machine based on C2 server command. Additionally, this threat also has a ransomware encryption/decryption module which appends .crimson extension.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0028
This query was originally published in the threat analytics report, Solorigate supply chain attack. Please note that these attacks are currently known as the Nobelium campaign.
Microsoft detects the 2020 SolarWinds supply chain attack implant and its other components as part of a campaign by the Nobelium activity group. Nobelium is the threat actor behind the attack against SolarWinds, which was previously referred to as Solorigate.
Nobelium silently added malicious code to legitimate software updates for Orion, which is IT monitoring software provided by SolarWinds. In this way, malicious dynamic link libraries (DLLs) were distributed to SolarWinds customers.
The following query detects events when Nobelium received a DNS response after launching a lookup request to known command-and-control infrastructure.
More Nobelium-related queries can be found listed under the See also section of this document.
References:
https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
https://www.microsoft.com/security/blog/2020/12/18/analyzing-solorigate-the-compromised-dll-file-that-started-a-sophisticated-cyberattack-and-how-microsoft-defender-helps-protect/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1028
'Detects suspicious user agent strings used by known hack tools'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
5028
'Detects request to potentially harmful file types (.ps1, .bat, .vbs, etc.).'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3028
Identify accounts that have logged on to affected endpoints.
Check for specific alerts.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0027
Action "PnpDeviceConnected" reports the connection of any plug and play device.
Read more online on event 6416: https://docs.microsoft.com/windows/security/threat-protection/auditing/event-6416.
Query #1: look for rare one-time devices connected to a specific machine.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1027
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2027
Remote Monitoring and Management (RMM) programs are IT to manage remote endpoints. Attackers have begun to abuse these programs to persist or provide C2 channels.
https://github.com/jischell-msft/RemoteManagementMonitoringTools
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0027
This hunting query looks Malware Hides Itself Among Windows Defender Exclusions to Evade Detection
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0027
'Under specific circumstances, executing KQL queries can exfiltrate information like access tokens, regarding external data functions like adx().
This query tries to list executed KQL queries that used the adx() function and where an access token might have been exposed to.
Ref: https://docs.microsoft.com/azure/azure-monitor/logs/azure-monitor-data-explorer-proxy
Ref: https://securecloud.blog/2022/04/27/azure-monitor-malicious-kql-query/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1027
These queries was originally published in the threat analytics report, Attacks on gov't, think tanks, NGOs.
As described further in Analysis of cyberattack on U.S. think tanks, non-profits, public sector by unidentified attackers, there was a very large spear-phishing campaign launched in November 2019.
The attackers would gain access to a target by having the user click on a link to a compromised website and download a .zip archive.
Once established on a target's device, the attackers used a malicious DLL named cyzfc.dat to execute additional payloads. They would call a function in the malicious DLL via the legitimate Windows process, rundll32.exe, to connect directly to their command-and-control (C2) servers.
The following queries detect activity associated with the malicious DLL, cyzfc.dat., used in this campaign.
Reference - https://docs.microsoft.com/windows-server/administration/windows-commands/rundll32
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
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