Detections

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

752 detections

The analytic identifies a spike in API activity related to the deletion of S3 buckets in an AWS environment. It uses AWS CloudTrail logs to detect anomalies by comparing current deletion activity against a historical baseline. Unusual spikes in S3 bucket deletions could indicate malicious actions such as data exfiltration or unauthorized data destruction, leading to significant data loss, disruption of services, and potential exposure of sensitive information. Immediate investigation is required to determine the legitimacy of the activity.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0049
The following analytic identifies when an O365 email account sends and then hard deletes an email to an external recipient within a short period (within 1 hour). This behavior may indicate a compromised account where the threat actor is attempting to remove forensic artifacts or evidence of exfiltration activity. This behavior is often seen when threat actors want to reduce the probability of detection by the compromised account owner.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0041
The following analytic detects excessive file deletion events in the Windows Defender folder. It leverages Sysmon EventCodes 23 and 26 to identify processes deleting multiple files within this directory. This behavior is significant as it may indicate an attempt to corrupt or disable Windows Defender, a key security component. If confirmed malicious, this activity could allow an attacker to disable endpoint protection, facilitating further malicious actions without detection.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1041
This analytic identifies a process attempting to delete its own executable file using `cmd.exe` and the `del` command. This behavior is often associated with defense evasion techniques employed by malware, such as Clop ransomware, to remove its executable file after execution or under specific conditions. Detecting such activity is crucial for identifying malicious actors trying to evade detection and complicate incident response efforts.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0041
The analytic detects the deletion of service files on a Linux machine within system directories (e.g., /etc/systemd/, /lib/systemd/, /run/systemd/). This activity is significant because attackers may delete or modify services to disable security features, evade defenses, impair system functionality, or execute a destructive payload. Immediate investigation is required to determine the responsible process and user.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0039
This analytic detects the deletion of the ConsoleHost_history.txt file, which stores command history for PowerShell sessions. Attackers may attempt to remove this file to cover their tracks and evade detection during post-exploitation activities. This detection focuses on file deletion commands executed via PowerShell, Command Prompt, or scripting languages that specifically target ConsoleHost_history.txt, typically located at %APPDATA%\Microsoft\Windows\PowerShell\PSReadline\ConsoleHost_history.txt. Identifying such activity can help uncover potential anti-forensic behavior and suspicious administrative actions.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0039
This analytic detects the execution of the 'shred' command on a Linux machine, which is used to overwrite files to make them unrecoverable. It leverages data from Linux Auditd, focusing on process names and command-line arguments. This activity is significant because the 'shred' command can be used in destructive attacks, such as those seen in the Industroyer2 malware targeting energy facilities. If confirmed malicious, this activity could lead to the permanent destruction of critical files, severely impacting system integrity and data availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects the deletion of cron jobs on a Linux machine. It leverages filesystem event logs to identify when files within the "/etc/cron.*" directory are deleted. This activity is significant because attackers or malware may delete cron jobs to disable scheduled security tasks or evade detection mechanisms. If confirmed malicious, this action could allow an attacker to disrupt system operations, evade security measures, or facilitate further malicious activities such as data wiping, as seen with the acidrain malware.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0036
The following analytic detects a high frequency of file deletions in the /boot/ folder on Linux systems. It leverages filesystem event logs to identify when 200 or more files are deleted within an hour by the same process. This behavior is significant as it may indicate the presence of wiper malware, such as Industroyer2, which targets critical system directories. If confirmed malicious, this activity could lead to system instability or failure, hindering the boot process and potentially causing a complete system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0035
The following analytic detects the deletion of init daemon scripts on a Linux machine. It leverages filesystem event logs to identify when files within the /etc/init.d/ directory are deleted. This activity is significant because init daemon scripts control the start and stop of critical services, and their deletion can indicate an attempt to impair security features or evade defenses. If confirmed malicious, this behavior could allow an attacker to disrupt essential services, execute destructive payloads, or persist undetected in the environment.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
This analytic detects the execution of the Windows OS tool cmdkey.exe with the /delete parameter. This activity is significant because cmdkey.exe can be used by attackers to delete stored credentials, potentially leading to privilege escalation and persistence. If confirmed malicious, this behavior could allow attackers to remove stored user credentials, hindering incident response efforts and enabling further unauthorized access to the compromised system.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0034
The following analytic detects a high frequency of file deletions in the /etc/ folder on Linux systems. It leverages the Endpoint.Filesystem data model to identify instances where 200 or more files are deleted within an hour, grouped by process name and process ID. This behavior is significant as it may indicate the presence of wiper malware, such as AcidRain, which aims to delete critical system files. If confirmed malicious, this activity could lead to severe system instability, data loss, and potential disruption of services.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
1033
The following analytic detects the deletion of critical directories on a Linux machine using the `rm` command with argument rf. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions targeting directories like /boot, /var/log, /etc, and /dev. This activity is significant because deleting these directories can severely disrupt system operations and is often associated with destructive campaigns like Industroyer2. If confirmed malicious, this action could lead to system instability, data loss, and potential downtime, making it crucial for immediate investigation and response.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0032
The following analytic detects the execution of a Unix shell command designed to wipe root directories on a Linux host. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on the 'rm' command with force recursive deletion and the '--no-preserve-root' option. This activity is significant as it indicates potential data destruction attempts, often associated with malware like Awfulshred. If confirmed malicious, this behavior could lead to severe data loss, system instability, and compromised integrity of the affected Linux host. Immediate investigation and response are crucial to mitigate potential damage.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0031
The analytic detects the deletion of SSL certificates on a Linux machine. It leverages filesystem event logs to identify when files with extensions .pem or .crt are deleted from the /etc/ssl/certs/ directory. This activity is significant because attackers may delete or modify SSL certificates to disable security features or evade defenses on a compromised system. If confirmed malicious, this behavior could indicate an attempt to disrupt secure communications, evade detection, or execute a destructive payload, potentially leading to significant security breaches and data loss.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0031
The analytic detects the execution of the 'shred' command on a Linux machine, which is used to overwrite files to make them unrecoverable. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because the 'shred' command can be used in destructive attacks, such as those seen in the Industroyer2 malware targeting energy facilities. If confirmed malicious, this activity could lead to the permanent destruction of critical files, severely impacting system integrity and data availability.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0031
The analytic detects the execution of a Unix shell command designed to wipe root directories on a Linux host. It specifically looks for the 'rm' command with force recursive deletion ('-rf') and the '--no-preserve-root' option. This activity indicates potential data destruction attempts, often associated with malware like Awfulshred. If confirmed malicious, this behavior could lead to severe data loss, system instability, and compromised integrity of the affected Linux host. Immediate investigation and response are crucial to mitigate potential damage.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0030
The following analytic detects the deletion of Linux service unit configuration files by suspicious processes. It leverages Endpoint Detection and Response (EDR) telemetry, focusing on processes executing the 'rm' command targeting '.service' files. This activity is significant as it may indicate malware attempting to disable critical services or security products, a common defense evasion tactic. If confirmed malicious, this behavior could lead to service disruption, security tool incapacitation, or complete system compromise, severely impacting the integrity and availability of the affected Linux host.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 year ago
0029
Detects when a GitHub repository is archived or deleted. This activity could indicate malicious intent, such as an attacker attempting to destroy evidence or disrupt development, or it could be a legitimate administrative action. Monitoring these events is crucial for maintaining code integrity and operational continuity.
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Google SecOps@GoogleSecOps
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Google SecOps Detection Rules
2 years ago
1028
Detects the deletion of files commonly used for backups by adversaries to prevent system recovery. This rule specifically looks for deletion actions performed by common Windows command-line interpreters and system utilities on files with backup-related extensions.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0059
Detects the deletion of files by the Sysinternals SDelete utility. It looks for the common name pattern used to rename files before deletion, specifically files ending with '.AAA' or '.ZZZ'.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
2 years ago
0023
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