Azure Sentinel

@AzureSentinel
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1,223 detections

'This query detects lateral movement using GPO scheduled task usually used to deploy ransomware at scale.
It monitors whether a scheduled task is modified within the Sysvol folder in GPO.
Ref: https://bogusecurity.com/2019/12/26/persistence-and-execution-at-scale-via-gpo-scheduled-task/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0040
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
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AzureSentinel
1 year ago
2039
This query was originally published in the threat analytics report, MailSniper Exchange attack tool.
MailSniper is a tool that targets Microsoft Exchange Server. The core function is to connect to Exchange Server and search through emails. In support of this, it can perform reconnaissance, collection, exfiltration, and credential theft. MailSniper is used both by red teams running penetration tests, and by malicious actors.
Microsoft Defender Security Center may record the following alerts during and after an attack:
1. Global mail search on Exchange using MailSniper
2. Exchange mailbox or mail folder search using MailSniper
3. Enumeration of Active Directory usernames using MailSniper
4. Enumeration of the Exchange GAL using MailSniper
5. Access to Exchange inboxes using MailSniper
6. Password spraying using MailSniper
7. Enumeration of domains and user accounts using MailSniper
The following query detects activity commonly associated with attacks run with MailSniper.
Reference - https://github.com/dafthack/MailSniper
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0039
'This detection will alert when RunningRAT URI parameters or paths are detect in an HTTP request.
Id the device blocked this communication presence of this alert means the RunningRAT implant is likely still executing on the source host.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0140
'This query looks for suspicious request patterns to Exchange servers that fit a pattern observed by Silk Typhoon actors.
The same query can be run on HTTPProxy logs from on-premise hosted Exchange servers.
Reference: https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0040
In this detection, we track emails with suspicious keywords in subjects.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1039
'Shows the rarest processes seen running for the first time. (Performs best over longer time ranges - eg 3+ days rather than 24 hours!)
These new processes could be benign new programs installed on hosts;
However, especially in normally stable environments, these new processes could provide an indication of an unauthorized/malicious binary that has been installed and run.
Reviewing the wider context of the logon sessions in which these binaries ran can provide a good starting point for identifying possible attacks.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1038
Attackers can use Adfind which is administrative tool to gather information about Domain controllers, ADFS Servers. They may also rename executables with other benign tools on the system.
Below query will look for adfind usage in commandline arguments irrespective of executable name in short span of time. You can limit query this to your DC and ADFS servers.
Below references talk about suspicious use of adfind by adversaries.
- https://thedfirreport.com/2020/05/08/adfind-recon/
- https://www.fireeye.com/blog/threat-research/2020/05/tactics-techniques-procedures-associated-with-maze-ransomware-incidents.html
- 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
0038
LemonDuck is an actively updated and robust malware primarily known for its botnet and cryptocurrency mining objectives. First discovered in 2019, LemonDuck has since adopted more sophisticated behavior and escalated its operations in 2021. Today, beyond using resources for its traditional bot and mining activities, LemonDuck steals credentials, removes security controls, spreads via emails, moves laterally, and ultimately drops more tools for human-operated activity.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0038
'Identifies modifications to user's MFA settings. An attacker could use access to modify MFA settings to bypass MFA requirements or maintain persistence.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
1039
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