Detections

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

752 detections

'Detect mass file deletion events within Azure File and Blob storage. deleteWindow controls
the period of time the deletions must occur in, whilst the deleteThreshold controls how many files
must be deleted within that threshold. Query works on a per-IP address basis, so will only detect a single
IP deleting multiple files.'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
13095
'This query looks for diagnostic settings that are removed from a resource.
This could indicate an attacker or malicious internal trying to evade detection before malicious act is performed.
If the diagnostic settings are being deleted as part of a parent resource deletion, the event is ignores.'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
3082
Detects the deletion of the TeamViewer log files which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
0011
Detects the deletion of the "Zone.Identifier" ADS. Attackers can leverage this in order to bypass security restrictions that make use of the ADS such as Microsoft Office apps.
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
009
Instead of running several queries separately, you can also use a comprehensive query that checks for multiple signs of ransomware activity to identify affected devices. The following consolidated query:
Looks for both relatively concrete and subtle signs of ransomware activity
Weighs the presence of these signs
Identifies devices with a higher chance of being targets of ransomware
When run, this consolidated query returns a list of devices that have exhibited multiple signs of attack. The count of each type of ransomware activity is also shown.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
4054
Detects the deletion of IIS WebServer access logs which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
008
'This hunting query will try to identify instances where a file us uploaded to file storage and then deleted
within a given threshold. By default the query will find instances where a file is uploaded and deleted within
5 minutes. This hunting query will help detect automated exfiltration.'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2052
This query identifies common processes run by ransomware
malware to destroy volume shadow copies or clean free
space on a drive to prevent a file from being recovered
post-encryption. To reduce false positives, results are
filtered to only actions taken when the initiating
process was launched from a suspicious directory. If
you don't mind false positives, consider removing the
last where clause.
Special thanks to Captain for additional inputs
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0047
This query looks for users performing file deletion activities. Spikes in file deletion observed from risky sign-in sessions are flagged here.
This applies to SharePoint and OneDrive users.
Audit event and Cloud application identifier references.
Reference - https://learn.microsoft.com/microsoft-365/compliance/audit-log-activities?view=o365-worldwide
Reference - https://learn.microsoft.com/azure/sentinel/entities-reference#cloud-application-identifiers
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0046
'This hunting query will identify where a file is uploaded to Azure File or Blob storage
and is then accessed once before being deleted. This activity may be indicative of
exfiltration activity.'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
2038
Detects the deletion of a prefetch file which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
006
This query was originally published in the threat analytics report, Ransomware continues to hit healthcare, critical services.
It finds all user accounts that have logged on to an endpoint affected by Cobalt Strike, a penetration tool.
Assume that all credentials on endpoints affected by Cobalt Strike were available to attackers and that all associated accounts are compromised. Note that attackers will not only dump credentials for accounts that have logged on to interactive or RDP sessions, but will also dump cached credentials and passwords for service accounts and scheduled tasks that are stored in the LSA Secrets section of the registry.
Reference - https://attack.mitre.org/software/S0154/
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0032
Detects the deletion of the event log files which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
005
Detects an unexpected file being deleted by dns.exe which my indicate activity related to remote code execution or other forms of exploitation as seen in CVE-2020-1350 (SigRed)
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
005
Detects the deletion of tomcat WebServer logs which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
005
'This detection looks for command line parameters associated with the use of Sysinternals sdelete (https://docs.microsoft.com/sysinternals/downloads/sdelete) to delete multiple files on a host's C drive.
A threat actor may re-name the tool to avoid detection and then use it for destructive attacks on a host.
This detection uses the ASIM imProcess parser, this will need to be deployed before use - https://docs.microsoft.com/azure/sentinel/normalization'
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0028
Identify accounts that have logged on to affected endpoints.
Check for specific alerts.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0027
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 attackers would compromise a web-facing endpoint and employ tools such as Cobalt Strike to steal users' credentials.
Cobalt Strike is commercial software used to conduct simulated threat campaigns against a target; however, malicious actors also use Cobalt Strike in real attacks. The software has a large range of capabilities, including credential theft.
The following query identifies accounts that have logged on to compromised endpoints and have potentially had their credentials stolen.
References:
https://www.microsoft.com/security/blog/2020/04/28/ransomware-groups-continue-to-target-healthcare-critical-services-heres-how-to-reduce-risk/
https://www.cobaltstrike.com/
https://attack.mitre.org/software/S0154/
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0026
This query identifies use of wmic.exe to delete shadow copy snapshots prior to encryption.
Azure Sentinel@AzureSentinel
avatar
AzureSentinel
1 year ago
0025
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 the use of the tool cipher.exe to delete indicators of malicious activity right before encrypting a drive.
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
1024
Detects the deletion of the PowerShell console History logs which may indicate an attempt to destroy forensic evidence
Yamato Security Hayabusa@YamatoSecurityHayabusa
avatar
Yamato Security Hayabusa Rules
1 year ago
004
Page 32 of 36