Detections

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

654 detections

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
Looking for high volume queries against a given RemoteIP, per DeviceName, RemotePort and Process.
Please change the Timestamp window according your preference/objective, as also the subnet ranges that you want to analyze against.
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0017
'This alerts when a client IP connects with 1-15 different useragents in less than 1 hour. Limited to 50 or less connections to avoid high traffic. May indicate malicious activity as a probing method.'
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0013
This query was originally published in the threat analytics report, Operation Soft Cell.
Operation Soft Cell is a series of campaigns targeting users' call logs at telecommunications providers throughout the world. These attacks date from as early as 2012.
Operation Soft Cell operators have been known to run nbtscan.exe, a legitimate MS-DOS command-line tool used to discover any NETBIOS nameservers on a local or remote TCP/IP network.
The following query detects any nbtscan activity on the system over the past seven days.
Reference - https://www.cybereason.com/blog/operation-soft-cell-a-worldwide-campaign-against-telecommunications-providers
Azure Sentinel@AzureSentinel
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AzureSentinel
1 year ago
0012
This analytic identifies internal systems that generate a high volume of intrusion detection events within a 30-minute window, specifically leveraging Cisco Secure Firewall Threat Defense logs. It counts hosts that trigger 15 or more Snort-based signatures. A sudden increase in intrusion alerts from a single host can indicate malicious activity such as malware execution, command-and-control communication, vulnerability scanning, or lateral movement. It may also be caused by misconfigured software. Systems exhibiting this pattern require prompt investigation as repeated Snort rule matches are often early indicators of compromise or active exploitation.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
40132
The following analytic identifies unauthenticated requests to Kubernetes cluster pods. It detects this activity by analyzing GCP Pub/Sub messages for audit logs where the response status code is 401, indicating unauthorized access attempts. This activity is significant for a SOC because it may indicate reconnaissance or scanning attempts by an attacker trying to identify vulnerable pods. If confirmed malicious, this activity could lead to unauthorized access, allowing the attacker to exploit vulnerabilities within the cluster, potentially compromising sensitive data or gaining control over the Kubernetes environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0092
This analytic identifies Snort intrusion signatures that have been triggered by ten or more distinct internal IP addresses within a one-hour window. It leverages Cisco Secure Firewall Threat Defense logs and focuses on the IntrusionEvent event type to detect activity that may indicate broad targeting or mass exploitation attempts. This behavior is often associated with opportunistic scanning, worm propagation, or automated exploitation of known vulnerabilities across multiple systems. If confirmed malicious, this could represent the early phase of a coordinated attack aiming to gain a foothold on several hosts or move laterally across the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
6079
This analytic detects an unusual number of Kerberos Ticket Granting Ticket (TGT) requests for non-existing users from a single source endpoint. It leverages Windows Event ID 4768 and identifies anomalies using the 3-sigma statistical rule. This behavior is significant as it may indicate an adversary performing a user enumeration attack against Active Directory. If confirmed malicious, the attacker could validate a list of usernames, potentially leading to further attacks such as brute force or credential stuffing, compromising the security of the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5064
The following analytic detects unauthenticated requests to an Amazon EKS Kubernetes cluster, specifically identifying actions by the "system:anonymous" user. It leverages AWS CloudWatch Logs data, focusing on user agents and authentication details. This activity is significant as it may indicate unauthorized scanning or probing of the Kubernetes cluster, which could be a precursor to an attack. If confirmed malicious, this could lead to unauthorized access, data exfiltration, or disruption of services within the Kubernetes environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0060
This analytic detects internal hosts triggering multiple IDS signatures, which may include either more than 25 signatures against a single host or a single signature across over 25 destination IP addresses. Such patterns can indicate active vulnerability scanning activities within the network. By monitoring IDS logs, this detection helps identify and respond to potential vulnerability scanning attempts, enhancing the network's security posture and preventing potential exploits.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
4058
This analytic detects unauthenticated requests made against the Kubernetes Pods API, specifically looking for events where the user is "system:anonymous", the verb is "list", the resource is "pods", and the request URI is "/api/v1/pods". This activity indicates potential unauthorized access attempts to enumerate Kubernetes pods within an Amazon EKS cluster. Such access could lead to sensitive resource discovery, unauthorized command execution, or lateral movement if exploited.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0057
The analytic identifies excessive security scanning activities in AWS by detecting a high number of Describe, List, or Get API calls from a single user. It leverages AWS CloudTrail logs to count distinct event names and flags users with more than 50 such events. This behavior is significant as it may indicate reconnaissance activities by an attacker attempting to map out your AWS environment. If confirmed malicious, this could lead to unauthorized access, data exfiltration, or further exploitation of your cloud infrastructure.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
4054
The following analytic detects potential scanning activities within a Kubernetes environment. It identifies unauthorized access attempts, probing of public APIs, or attempts to exploit known vulnerabilities by monitoring Kubernetes audit logs for repeated failed access attempts or unusual API requests. This activity is significant for a SOC as it may indicate an attacker's preliminary reconnaissance to gather information about the system. If confirmed malicious, this activity could lead to unauthorized access to sensitive systems or data, posing a severe security risk.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
2047
The analytic identifies potential scanning activities within a Kubernetes environment by unauthenticated IP addresses. It leverages Kubernetes audit logs to detect multiple unauthorized access attempts (HTTP 403 responses) from the same source IP. This activity is significant as it may indicate an attacker probing for vulnerabilities or attempting to exploit known issues. If confirmed malicious, such scanning could lead to unauthorized access, data breaches, or further exploitation of the Kubernetes infrastructure, compromising the security and integrity of the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0040
The analytic detects a high volume of Kerberos service ticket requests (more than 30) from a single source within a 5-minute window, specifically focusing on requests with computer names as the Service Name (Event ID 4769). This behavior may indicate malicious activities such as lateral movement, malware staging, or reconnaissance, potentially leading to unauthorized access and network compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0033
The following analytic identifies specific GET or HEAD requests to web servers that indicate reconnaissance attempts to find vulnerable JBoss servers. It leverages data from the Web data model, focusing on HTTP methods and URLs associated with JBoss management interfaces. This activity is significant because it often precedes exploitation attempts using tools like JexBoss, which can compromise the server. If confirmed malicious, attackers could gain unauthorized access, execute arbitrary code, or escalate privileges, leading to potential data breaches and system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0030
Detects the execution of NimScan, a port scanning utility. This rule identifies NimScan based on its executable name ('NimScan.exe') and specific IMPHASH values associated with different versions of the tool. Adversaries have been observed using this utility to scan for open ports on remote hosts within compromised environments.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1019
Identify enumeration of inboxes across the Entra ID tenant. This detection is based on the Invoke-GraphOpenInboxFinder in GraphRunner but the concepts are applicable to other tools that scan for accessible inboxes.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
2 years ago
000
This rule detects when an OpenCanary honeypot's NTP service receives a 'monlist' request. The 'monlist' command is a deprecated feature in NTP that can be abused for amplification attacks (Network Denial of Service). Detecting this activity on a honeypot indicates an adversary is likely scanning for vulnerable NTP servers or attempting to use the honeypot in an amplification attack.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0020
Amazon GuardDuty detects a Denial of Service (DoS) activity in an Amazon EC2 instance.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
2 years ago
000
Detects the execution of common network scanning and reconnaissance tools on Linux systems. These tools are often used by adversaries to enumerate local or remote network services, identify open ports, and gather information about network topology and available hosts. The rule specifically looks for the execution of tools like netcat (when not in listen mode), nmap, hping, naabu, autorecon, and telnet.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
1022
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