Detections

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

40,056 detections

The following analytic identifies security events from Microsoft Defender, focusing on Exploit Guard and Attack Surface Reduction (ASR) features. It detects Event IDs 1121, 1126, 1131, and 1133 for blocked operations, and Event IDs 1122, 1125, 1132, and 1134 for audit logs. Event ID 1129 indicates user overrides, while Event ID 5007 signals configuration changes. This detection uses a lookup to correlate ASR rule GUIDs with descriptive names. Monitoring these events is crucial for identifying unauthorized operations, potential security breaches, and policy enforcement issues. If confirmed malicious, attackers could bypass security measures, execute unauthorized actions, or alter system configurations.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 month ago
003
The following analytic detects the disabling of important audit policies. It leverages EventCode 4719 from Windows Security Event Logs to identify changes where success or failure auditing is removed. This activity is significant as it suggests an attacker may have gained access to the domain controller and is attempting to evade detection by tampering with audit policies. If confirmed malicious, this could lead to severe consequences, including data theft, privilege escalation, and full network compromise. Immediate investigation is required to determine the source and intent of the change.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 month ago
003
The following analytic detects the creation or connection to known suspicious C2 named pipes.
It leverages Sysmon EventCodes 17 and 18 to identify known default pipe names used by C2 tools.
If confirmed malicious, this could allow an attacker to abuse these to potentially gain persistence, command and control, or further system compromise.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 month ago
203
Detects instances where a process that is not a recognized web browser (chrome, msedge, firefox, brave, opera, or explorer) accesses multiple unique browser cookie files. This is a common pattern for credential harvesting malware attempting to steal browser sessions.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
5010
This rule monitors endpoint telemetry for indicators of compromise (IOCs) associated with known malicious activity. It checks for file creation, process execution, and network connections that match a defined list of malicious file hashes (SHA256, SHA1, MD5), C2 IP addresses, and malicious domains or URL patterns.
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Arnold Chan@slaz
Defender - KQL
1 month ago
302
Detects runtime processes associated with AI agents or scripting environments (e.g., python, node, deno) accessing sensitive credential storage paths and files, such as SSH keys, cloud provider configuration directories, and local environment variables, which may indicate credential exfiltration.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
5011
Detects a suspected ClickFix social engineering attack where a user is tricked into pasting malicious commands into Windows Terminal, leading to a PowerShell download, followed by the appearance of specific known malicious artifacts (LockScreenContentServer.exe, dui70.dll, or 1.bat) within 15 minutes on the same device.
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Arnold Chan@slaz
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Midnight Slayer
1 month ago
109
This rule monitors the software inventory for vulnerable versions of OpenSSL and WolfSSL libraries. Specifically, it flags instances of WolfSSL prior to version 5.9.4, which are susceptible to peer-authentication bypass vulnerabilities. The rule is intended for patch management and asset exposure tracking rather than detecting active exploitation.
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Ankit Mehta@Secvyn
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SlimKQL
1 month ago
8011
Detects potentially malicious use of rundll32.exe by monitoring for execution from suspicious directory paths (e.g., Temp, AppData, Downloads), execution with arguments missing common legitimate entry points, unexpected network connections originating from rundll32.exe, or rundll32.exe spawning child processes (excluding known safe binaries like conhost.exe or werfault.exe).
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
7010
This rule detects various malicious indicators including known file hashes, IP addresses, domains, and specific URLs associated with threat activity. It consolidates hits from process, file, and network telemetry to alert on potential compromise or communication with identified command-and-control (C2) infrastructure.
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Arnold Chan@slaz
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Detection & Hunting Community
1 month ago
1011
Detects persistence attempts using common Windows auto-start registry keys or scheduled tasks where the initiating process is unsigned or has an invalid signature. The rule focuses on binaries executing from suspicious, user-writable directories (e.g., Temp, AppData, Downloads) and specifically targets persistence mechanisms involving the 'SecurityHealthService.exe' filename.
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Arnold Chan@slaz
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Detections.ai Community
1 month ago
005
Detects modifications to the Windows Subsystem for Linux (WSL) InstallLocation registry key.
Attackers can modify this registry key to redirect the execution flow of legitimate WSL processes (wsl.exe or bash.exe) to a malicious payload, acting as a proxy execution and defense evasion technique.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 month ago
006
Detects exploitation attempts against Microsoft SharePoint leveraging the ToolShell exploit chain, as well as subsequent post-exploitation webshell activity involving anomalous 'layoutNsp.aspx' naming conventions. This covers initial exploitation of vulnerabilities such as CVE-2025-49704 and associated variants, followed by the deployment of webshells associated with the ToolShell campaign.
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Arnold Chan@slaz
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Detection & Hunting Community
1 month ago
005
Detects exploitation attempts against Microsoft SharePoint leveraging the ToolShell exploit chain, as well as subsequent post-exploitation webshell activity involving anomalous 'layoutNsp.aspx' naming conventions. This covers initial exploitation of vulnerabilities such as CVE-2025-49704 and associated variants, followed by the deployment of webshells associated with the ToolShell campaign.
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Arnold Chan@slaz
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Detections.ai Community
1 month ago
205
This rule detects potential Browser-in-the-Browser (BitB) phishing attacks by identifying suspicious browser pop-up behavior (using window.open flags, hidden address/toolbars) on non-identity-provider domains, followed shortly by credential submission patterns on the same device. This pattern mimics legitimate OAuth or SSO windows to harvest user credentials.
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
4014
Detects potential exploitation attempts targeting the vulnerable Oracle PeopleSoft PSEMHUB Environment Management Hub endpoint (associated with CVE-2026-35273 and UNC6240). The rule identifies suspicious bursts of POST requests where the URI path uses percent-encoding or mixed-case characters to evade Web Application Firewall (WAF) filtering.
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Ankit Mehta@Secvyn
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SlimKQL
1 month ago
7024
Detects a sequence of events where a user clicks a shared link to an AI chatbot conversation followed closely (within 15 minutes) by the execution of potentially malicious processes (mshta, powershell, cmd) that include suspicious command-line patterns indicative of ClickFix-style social engineering.
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Arnold Chan@slaz
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Detections.ai Community
1 month ago
509
Detects indicators associated with the ChatGPT Custom GPT ClickFix campaign across process, network connection, DNS, and HTTP telemetry: known malicious file hashes, C2 IP addresses, the chattypetty.com domain, and known payload-hosting URLs.
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Arnold Chan@slaz
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Hunters
1 month ago
0010
Detects a suspicious pattern where a user authenticates to a remote access portal (like Citrix or VPN) without multi-factor authentication (MFA) or with an existing risk flag, followed by a surge in file activity (creation, modification, or renaming of >500 files or >200 distinct files) on the same account within a 24-hour window, potentially indicating compromised credential usage for staging data for exfiltration or ransomware.
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Ankit Mehta@Secvyn
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SlimKQL
1 month ago
10020
Detects browser processes performing JSON-RPC network connections to known public blockchain node providers, a network behavior characteristic of the EtherHiding technique used by the ErrTraffic MaaS platform to resolve C2 infrastructure via smart contracts. This rule identifies the network-side beaconing and should be correlated with suspicious process execution chains (e.g., browser-spawned PowerShell/cmd).
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Ibrahim Saud@tektrix
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Detections.ai Community
1 month ago
3121
The following analytic detects a user account modifying its own userPrincipalName (UPN) to match the sAMAccountName of another account via Windows Security Event 4738.
This is the setup step of the ResetNightmare attack (CVE-2026-27912), where an attacker with WriteProperty rights on their own UPN attribute spoofs their identity to a target account.
The KDC then resolves a ptype=10 (NT-ENTERPRISE) Kerberos pre-authentication request against the spoofed UPN, issuing a kadmin/changepw TGT that can be used to change the target account's password via kpasswd (port 464).
Event 4738 is generated when a user account attribute is changed. This analytic filters to events where the SubjectUserSid equals the TargetSid (self-modification), the new UPN value is not a standard UPN (no @ sign), and the value is not a Windows placeholder.
A non-UPN value set on one's own account is anomalous and has no legitimate administrative use case.
Splunk Security@SplunkSecurity
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Splunk Security Content
1 month ago
507
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