Detections

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

4,308 detections

Private Key Files.
This query identifies file operation with files having.
One of the extensions commonly used to save a private.
Key. The risk is that if an attacker were to obtain.
The file, they could brute force any password on it.
And potentially obtain a powerful certificate. To do.
This, they would only need to obtain read access to.
The file.
The risk associated with these files is heavily.
Determined by the value of the certificate. For example,.
Loss of a self-signed certificate created by Adobe Acrobat.
Is significantly less impactful than loss of a website.
SSL certificate.
Recommendation: Know where these files are, and if possible.
Back them up and remove them. You might also consider.
Creating an informational alert.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1032
'This query identifies whether an Active Directory user object was assigned a service principal name which could indicate that an adversary is preparing for performing Kerberoasting.
This query checks for event id 5136, that the Object Class field is "user" and the LDAP Display Name is "servicePrincipalName".
Ref: https://thevivi.net/assets/docs/2019/theVIVI-AD-Security-Workshop_AfricaHackon2019.pdf'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1032
Query #1: Look for public IP addresses that failed to logon to a computer multiple times, using multiple accounts, and eventually succeeded.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
6030
This query was originally published in the threat analytics report, WDigest credential harvesting.
WDigest is a legacy authentication protocol dating from Windows XP. While still used on some corporate networks, this protocol can be manipulated by attackers to dump system credentials.
The Microsoft Security Response Center published an overview of KB2871997, which addresses WDigest use on older platforms. More recent versions of Windows can be protected with a holistic security approach that follows the principle of least privilege.
The following query returns any attempts to turn WDigest credential caching on through the registry.
References:
https://docs.microsoft.com/previous-versions/windows/it-pro/windows-server-2003/cc778868(v=ws.10)?redirectedfrom=MSDN
https://msrc-blog.microsoft.com/2014/06/05/an-overview-of-kb2871997/
https://www.catalog.update.microsoft.com/Search.aspx?q=KB2871997
https://docs.microsoft.com/windows-server/identity/ad-ds/plan/security-best-practices/implementing-least-privilege-administrative-models
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0030
This query was originally published in the threat analytics report, Msiexec abuse.
Msiexec.exe is a Windows component that installs files with the .msi extension. These kinds of files are Windows installer packages, and are used by a wide array of legitimate software. However, malicious actors can re-purpose msiexec.exe for living-off-the-land attacks, where they use legitimate system binaries on the compromised device to perform attacks.
The following query detects activity associated with misuse of msiexec.exe, particularly alongside mimikatz, a common credential dumper and privilege escalation tool.
Reference - https://www.varonis.com/blog/what-is-mimikatz/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1029
'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
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
'Identifies where Privileged Accounts have updated passwords or security information. This is joined with UEBA alerts to filter to only those accounts with a high investigation priority.
Ref : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-privileged-accounts#things-to-monitor'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0028
'Identifies privileged accounts that have been locked out. Verify these lockout are due to legitimate user activity and not due to threat actors attempting to access the accounts.
Ref : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-privileged-accounts#things-to-monitor'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2028
'Identifies spikes in failed sign-in events based on the volume of failed sign-in events over time. Use to identify patterns of suspicious behavior such as unusually high failed sign-in attempts from certain users.
Ref : https://docs.microsoft.com/azure/active-directory/fundamentals/security-operations-user-accounts'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2028
'Identifies an interrupted sign-in session from a country the user has not sign-in before in the last 7 days, where the password was correct. Although the session is interrupted by other controls such as multi factor authentication or conditional access policies, the user credentials should be reset due to logs indicating a correct password was observed during sign-in.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
6028
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
'This hunting query uses Application events from the "MSSQL$MICROSOFT##WID" provider to collect SQL statements run against an AD FS database (e.g Windows Internal Database (WID)).
A threat actor might want to extract the AD FS data configuration settings with a SQL statement or modify it with an UPDATE SQL statement.
In order to use this query you need to create a server audit and database audit specification on your AD FS database.
Reference: https://github.com/Azure/SimuLand/blob/main/3_simulate_detect/credential-access/exportADFSTokenSigningCertificate.md
Reference: https://o365blog.com/post/adfs/
'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2027
'Query shows 1200+ failed attempts by cIP per hour on server, then successful logon. Only includes > 1 user agent string or port. Could indicate successful probing and brute force success on IIS servers.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1027
'This query identifies Active Directory computer objects modifications that allow an adversary to abuse the Resource-based constrained delegation.
This query checks for event id 5136 that the Object Class field is "computer" and the LDAP Display Name is "msDS-AllowedToActOnBehalfOfOtherIdentity" which is an indicator of Resource-based constrained delegation.
Ref: https://shenaniganslabs.io/2019/01/28/Wagging-the-Dog.html'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
3027
Microsoft Defender for Identity raises alert on suspicious Kerberos ticket, pointing to a potential overpass-the-hash attack.
Once attackers gain credentials for a user with higher privileges, they will use the stolen credentials to sign into other devices and move laterally.
This query finds related sign-in events following overpass-the-hash attack to trace the footprint of the impersonated user.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
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
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AzureSentinel
1 year ago
0026
This query shows attempts to request Kerberos service ticket using the AS service, to monitor Kerberos AS authentications.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
'This identifies failed logon attempts using permutations based on known first and last names within 10m time windows. Iteration through separators or order changes in the logon name may indicate potential Brute Force logon attempts.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
'Identifies a list of IP addresses with a minimum number(default of 5) of failed logon attempts to remote hosts.
Uses that list to identify any successful logons to Microsoft Entra ID from these IPs within the same timeframe.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1026
Looks for users who had a risky sign in (based on Entra ID Identity Protection risk score) and then performed and ElevateAccess action. ElevateAccess operations can be used by Global Admins to obtain permissions over Azure resources.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0025
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