Detections

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

289 detections

Detects the creation of a new local user on a Fortinet FortiGate Firewall. The new local user could be used for VPN connections.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0093
Detects the modification of a user group on a Fortinet FortiGate Firewall. This activity could be used by an attacker to grant themselves or other malicious accounts VPN access to a network, facilitating persistence or privilege escalation.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0076
Detects the addition of firewall address objects on a Fortinet FortiGate Firewall. This activity could indicate an adversary attempting to modify network access controls to facilitate command and control, data exfiltration, or to bypass existing security policies.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1068
Detects the addition of a new VPN SSL Web Portal on a Fortinet FortiGate Firewall. This activity can be an indicator of an adversary establishing persistence or initial access, especially when observed in conjunction with other modifications to VPN SSL settings. Attackers might add new web portals to maintain access to the network or to create new entry points.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0062
Detects the addition of a new firewall policy on a Fortinet FortiGate Firewall. This activity could indicate an adversary attempting to alter network access controls for defense evasion, persistence, or to facilitate further malicious activity.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0055
Detects communication to known Command and Control (C2) servers associated with the Equation Group, as identified in the operational notes from the ShadowBrokers leak. This rule specifically looks for network connections to or from the hardcoded IP addresses linked to Equation Group C2 infrastructure.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0044
The following analytic detects the use of default or publicly known named pipes associated with Cobalt Strike. It leverages Sysmon EventID 17 and 18 to identify specific named pipes commonly used by Cobalt Strike's Artifact Kit and Malleable C2 Profiles. This activity is significant because Cobalt Strike is a popular tool for adversaries to conduct post-exploitation tasks, and identifying its named pipes can reveal potential malicious activity. If confirmed malicious, this could indicate an active Cobalt Strike beacon, leading to unauthorized access, data exfiltration, or further lateral movement within the network.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
100247
Detects potential exploitation of Cisco SNMP vulnerability (CVE-2025-20352) by identifying shell command patterns within SNMP traffic, indicative of remote code execution attempts as seen in Operation Zero Disco.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
40169
This analytic detects suspicious data transfer activities involving the use of the `split` syscall with the `-b` option, which specifies the size of each output file. This technique can be used by attackers to evade detection by breaking large files into smaller parts, bypassing size-based security controls, and facilitating covert exfiltration of sensitive data. By monitoring for unusual or unauthorized use of the `split` syscall with a specified block size, this analytic helps identify potential data exfiltration attempts.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0087
This analytic identifies the bulk creation of ransomware notes (e.g., .txt, .html, .hta files) on an infected machine. It leverages Sysmon EventCode 11 to detect multiple instances of these file types being created within a short time frame (10 seconds). A detection is triggered if 15 or more unique readme paths are observed. This activity is a strong indicator of an active ransomware attack, where the attacker is notifying the victim of the encryption. If confirmed malicious, this behavior could lead to widespread data encryption, rendering critical files inaccessible and potentially causing significant operational disruption.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1160
The following analytic detects suspicious attempts to find credentials stored in password stores, indicating a potential attacker's effort to access sensitive login information. Password stores are critical repositories that contain valuable credentials, and unauthorized access to them can lead to significant security breaches. By monitoring for unusual or unauthorized activities related to password store access, this analytic helps identify potential credential theft attempts, allowing security teams to respond promptly and prevent unauthorized access to critical systems and data.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0056
The following analytic identifies the execution of RAR utilities to archive files on a system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, GUIDs, and command-line arguments. This activity is significant as threat actors, including red-teamers and malware like DarkGate, use RAR archiving to compress and exfiltrate collected data from compromised hosts. If confirmed malicious, this behavior could lead to the unauthorized transfer of sensitive information to command and control servers, posing a severe risk to data confidentiality and integrity.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1042
Detects HTTP responses containing JavaScript associated with ClickFix phishing kits. These kits manipulate the DOM to mimic browser verification pages and trick users into copying and executing malicious commands.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
21177
Detects potential exploitation attempts against FortiWeb CVE-2025-52970. The detection looks for individual HTTP GET requests to a specific API endpoint with a crafted APSCOOKIE_FWEB cookie containing 'Era=9'. The rule enriches alerts with information about known malicious IPs without strictly filtering on them.
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Reyben Cortes@Reybendetecc
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Detections.ai Community
1 year ago
22145
Detects Acreed infostealer's cryptocurrency clipper activity. This rule identifies when a host first communicates with a known Acreed C2 domain (`trustdomainnet.live`) to fetch malicious wallet addresses, and then communicates with a QR code generation API (`api.zile42o.dev`) used to replace legitimate QR codes with malicious ones.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
1094
Detects attempts to bypass authentication in Fortra GoAnywhere MFT by exploiting a vulnerability (CVE-2025-10035). This is achieved by sending a crafted GET request to the Unlicensed.xhtml endpoint to trigger an exception and obtain a valid license request token, which is a prerequisite for further exploitation.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
00113
This analytic detects instances where an internal host attempts to communicate with over 500 ports on a single destination IP address. It includes filtering criteria to exclude applications performing scans over ephemeral port ranges, focusing on potential reconnaissance or scanning activities. Monitoring network traffic logs allows for timely detection and response to such behavior, enhancing network security by identifying and mitigating potential threats promptly.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
70108
This analytic detects intrusion events from known threat activity using Cisco Secure Firewall Intrusion Events. It leverages Cisco Secure Firewall Threat Defense IntrusionEvent logs to identify cases where one or multiple Snort signatures associated with a known threat or threat actor activity have been triggered within a one-hour time window. The detection uses a lookup table (cisco_snort_ids_to_threat_mapping) to map Snort signature IDs to known threat actors and their techniques. When multiple signatures associated with the same threat actor are triggered within the time window, and the count of unique signatures matches or exceeds the expected number of signatures for that threat technique, an alert is generated. This helps identify potential coordinated threat activity in your network environment by correlating related intrusion events that occur in close temporal proximity. Currently, this detection will alert on the following threat actors or malware families as defined in the cisco_snort_ids_to_threat_mapping lookup: ArcaneDoor, Static Tundra, AgentTesla, Amadey, AsyncRAT, Chafer, DCRAT, Lumma Stealer, Nobelium, Quasar, Remcos, Snake, Xworm. To add or update threat actors, update the cisco_snort_ids_to_threat_mapping.csv lookup file with new or modified threat names and associated Snort signature IDs.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5062
Detects potential remote code execution via a malicious OAuth URL in the mcp-remote proxy tool, indicative of CVE-2025-6514 exploitation.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
20114
This analytic detects the configuration of TFTP services on Cisco IOS devices that could be used to exfiltrate sensitive configuration files. Threat actors like Static Tundra have been observed configuring TFTP servers to make device configuration files accessible for exfiltration after gaining initial access. The detection specifically looks for commands that expose critical configuration files such as startup-config, running-config, and other sensitive system information through TFTP. This activity is particularly concerning as it may represent an attempt to steal credentials, network topology information, and other sensitive data stored in device configurations.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1059
This analytic detects the creation or modification of network interfaces on Cisco devices, which could indicate an attacker establishing persistence or preparing for lateral movement. After gaining initial access to network devices, threat actors like Static Tundra often create new interfaces (particularly loopback interfaces) to establish covert communication channels or maintain persistence. This detection specifically looks for the configuration of new interfaces, interface state changes, and the assignment of IP addresses to interfaces. These activities are particularly concerning when they involve unusual interface names or descriptions containing suspicious terms.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
5058
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