Detections

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

233 detections

This query helps in reviewing top policies for user overrides (Allow/Block)
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0021
As described in previous guidance, Nobelium may re-purpose legitimate existing OAuth Applications in the environment to their own ends. However, malicious activity patterns may be discernable from legitimate ones.
The following query returns OAuth Applications that access mail both directly and via Graph, allowing review of whether such dual access methods follow expected use patterns.
Reference - https://msrc-blog.microsoft.com/2020/12/13/customer-guidance-on-recent-nation-state-cyber-attacks/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
This query helps hunting for email conversation take over attempts
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2035
'Identifies when multiple (more than one) users mailboxes are configured to forward to the same destination.
This could be an attacker-controlled destination mailbox configured to collect mail from multiple compromised user accounts.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1035
This query helps you review all OAuth applications accessing user mail via Graph. It could return a significant number of results depending on how many applications are deployed in the environment.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0034
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 hunting query looks for hosts exporting a mailbox from an on-prem Exchange server, followed by
that same host removing the export within a short time window. This pattern has been observed by attackers
when exfiltrating emails from a target environment. A Mailbox export is unlikely to be a common command run so look for
activity from unexpected hosts and accounts.
Reference: https://www.volexity.com/blog/2020/12/14/dark-halo-leverages-solarwinds-compromise-to-breach-organizations/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1031
This query visualises total emails with Malware detections summarizing the data by ThreatNames of the malware detected.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1031
This query helps reviewing emails accessed by end users using cloud app events data
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0029
Hunting for credential phishing using the "Referral" infrastructure using Defender for Office 365 data
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0026
This query correlates Microsoft Defender for Office 365 signals and Microsoft Entra ID identity data to find the relevant endpoint event BrowerLaunchedToOpen in Microsoft Defender ATP.
This event reflects relevant clicks on the malicious URL in the spear-phishing email recognized by Microsoft Defender for Office 365.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1023
Identify prior activity from this campaign using IOCs shared by Microsoft's Threat Intelligence Center, or MSTIC.
Read more: https://blogs.microsoft.com/on-the-issues/2020/10/28/cyberattacks-phosphorus-t20-munich-security-conference/
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0022
The MailItemsAccessed action is part of the new Advanced Audit functionality of Microsoft Defender XDR. It's part of Exchange mailbox auditing and is enabled by default for users that have an Office 365 or Microsoft 365 E5 license, or for organizations with a Microsoft 365 E5 Compliance add-on subscription.
If more than 1,000 MailItemsAccessed audit records are generated in less than 24 hours, Exchange Online will stop generating auditing records for MailItemsAccessed activity. When a mailbox is throttled, MailItemsAccessed activity will not be logged for 24 hours after the mailbox was throttled. If this occurs, there's a potential that mailbox could have been compromised during this period. The recording of MailItemsAccessed activity will be resumed following a 24-hour period.
The query is looking for MailItemsAccessed Throttling events where the operation is done by a ClientApplication.
See The MailItemsAccessed mailbox auditing action.
Reference - https://docs.microsoft.com/microsoft-365/compliance/mailitemsaccessed-forensics-investigations?view=o365-worldwide#the-mailitemsaccessed-mailbox-auditing-action
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0022
This hunting query looks for hosts exporting a mailbox from an on-prem Exchange server, followed by
that same host removing the export within a short time window. This pattern has been observed by attackers
when exfiltrating emails from a target environment. A Mailbox export is unlikely to be a common command run so look for
activity from unexpected hosts and accounts.
Reference: https://www.volexity.com/blog/2020/12/14/dark-halo-leverages-solarwinds-compromise-to-breach-organizations/
Query insprired by Azure Sentinel detection https://github.com/Azure/Azure-Sentinel/blob/master/Hunting%20Queries/SecurityEvent/HostExportingMailboxAndRemovingExport.yaml
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
2022
This query helps report on who Previewed/Downloaded email messages using the Email entity page in Defender for Office 365
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0019
Use this query to find attempts to access files in the local path containing Outlook emails.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0017
// Author: jan geisbauer
// @janvonkirchheim
// ------------------------
// 1. A list of all devices that have this vulnerability
// 2. A list of all users that uses those devices
// 3. If these users received .mkv files recently
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0014
This query helps report on email access by administrators
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0014
Use this query to find email stealing activities ran by Qakbot that will use "ping.exe -t 127.0.0.1" to obfuscate subsequent actions.
Email theft that occurs might be exfiltrated to operators and indicates that the malware completed a large portion of its automated activity without interruption.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0013
In this query, we are looking for emails containing malware attachment sent by an internal sender
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0012
Use this query to find email stealing activities ran by Qakbot that will use "ping.exe -t 127.0.0.1" to obfuscate subsequent actions.
Email theft that occurs might be exfiltrated to operators and indicates that the malware completed a large portion of its automated activity without interruption.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0010
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