Detections

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

4,917 detections

This rule correlates Microsoft Defender for Endpoint (MDE) SmartScreen and Network Protection blocks with network activity logs. It specifically looks for instances where SmartScreenUrlWarning or ExploitGuardNetworkProtectionBlocked events occur due to 'CustomBlockList' or 'CustomPolicy' settings. The rule then joins these events with DeviceNetworkEvents to identify the associated URLs, remote IP addresses, and ports involved in the blocked network communication. The primary goal is to identify and provide context for network access attempts that are blocked by custom security policies, indicating potential malicious or unwanted website access.
avatar
Luis Zavier Guzman Garcia@KillBillKill98
avatar
Detections.ai Community
1 year ago
10137
This rule detects emails containing URLs that match domains identified as phishing domains by cert.pl. It joins email URL information with a regularly updated list of known malicious domains from cert.pl and then correlates these with email events to identify potential phishing attempts.
avatar
Benjamin Zulliger@benscha
avatar
Detections.ai Community
1 year ago
33196
Detects DNS queries to domains within known low reputation Effective Top-Level Domains (eTLDs). These eTLDs are often associated with malicious activities such as command and control, phishing, or malware distribution. The rule leverages a curated list of suspicious eTLDs, which is updated periodically.
avatar
SigmaHQ Detections@sigmaHQ
avatar
SigmaHQ
1 year ago
0024
Detects network connections to the 'webhook.site' domain, which is used as an exfiltration endpoint by the 'Shai-Halud' supply chain attack campaign. The risk score is elevated if the specific malicious URL path is observed.
avatar
Tim Peck@timpeck
avatar
Detections.ai Community
1 year ago
01215
Detects a user password change synced from on-premises Active Directory, immediately followed by the same user registering a new MFA method. This sequence is highly suspicious for existing privileged accounts and was used by the threat actor Storm-0501 to compromise a Global Administrator account that previously lacked MFA.
avatar
Jehad AbuSultan@Jabusultan
avatar
Detections.ai Community
1 year ago
62212
This analytic identifies the creation of suspicious .aspx or .ashx files in known drop locations for Exchange exploitation. Specifically, it targets paths associated with HAFNIUM group activity and vulnerabilities like ProxyShell and ProxyNotShell. This activity is a strong indicator of web shell deployment, a common method for persistent access and remote code execution. Successful exploitation could lead to unauthorized access, arbitrary command execution, and privilege escalation within the Exchange environment.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
1052
This detection identifies potentially suspicious usage of sqlcmd.exe, focusing on command patterns that may indicate data exfiltration, reconnaissance, or malicious database operations. The detection looks for both short-form (-X) and long-form (--flag) suspicious parameter combinations, which have been observed in APT campaigns targeting high-value organizations. For example, threat actors like CL-STA-0048 have been known to abuse sqlcmd.exe for data theft and exfiltration from compromised MSSQL servers. The detection monitors for suspicious authentication attempts, output redirection, and potentially malicious query patterns that could indicate unauthorized database access or data theft.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0040
This rule identifies unusual activity from locations not previously observed for a user within a defined lookback period. It leverages Microsoft Entra ID (Azure AD) Behavior Analytics and SigninLogs to baseline legitimate user locations and filter out trusted devices/IPs. The rule flags unusual activity where the source IP location is new for the user and exceeds a configurable threshold of 'unusual' behavior indicators, while also excluding specified trusted countries.
avatar
Dylan Evans@decksy
Dexter's Laboratory
1 year ago
549595
The following analytic identifies attempts to access the Remote ShellServlet on a web server, specifically targeting Confluence servers vulnerable to CVE-2023-22518 and CVE-2023-22515. It leverages web data to detect URLs containing "*plugins/servlet/com.jsos.shell/*" with a status code of 200. This activity is significant as it is commonly associated with web shells and other malicious behaviors, potentially leading to unauthorized command execution. If confirmed malicious, attackers could gain remote code execution capabilities, compromising the server and potentially the entire network.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0035
Detects potential remote code execution via a malicious OAuth URL in the mcp-remote proxy tool, indicative of CVE-2025-6514 exploitation.
avatar
Tim Peck@timpeck
avatar
Detections.ai Community
1 year ago
20114
This analytic detects unexpected outbound network connections initiated by known webserver processes such as `httpd.exe`, `nginx.exe`, or `tomcat.exe` to common file sharing or public content hosting services like GitHub, Discord CDN, Transfer.sh, or Pastebin. Webservers are rarely expected to perform outbound downloads, especially to dynamic or anonymous file hosting domains. This behavior is often associated with server compromise, where an attacker uses a reverse shell, webshell, or injected task to fetch malware or tools post-exploitation. The detection leverages Cisco Network Visibility Module flow data, enriched with process context, to identify this highly suspicious behavior.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0034
The analytic detects long URLs containing multiple SQL commands, indicating a potential SQL injection attack. This detection leverages web traffic data, specifically targeting web server destinations with URLs longer than 1024 characters or HTTP user agents longer than 200 characters. SQL injection is significant as it allows attackers to manipulate a web application's database, potentially leading to unauthorized data access or modification. If confirmed malicious, this activity could result in data breaches, unauthorized access, and complete system compromise. Immediate investigation and validation of alerts are crucial to mitigate these risks.
Splunk Security@SplunkSecurity
avatar
Splunk Security Content
1 year ago
0034
Detects the creation of a malicious executable named 'My Pictures.exe' on a removable drive, a technique used by VenomRAT for lateral movement.
avatar
Tim Peck@timpeck
avatar
Detections.ai Community
1 year ago
0037
Detects network connections to known malicious AnyDesk-related URLs and IP addresses, as well as the presence of specific malicious file hashes and filenames associated with AnyDesk-themed phishing or malware. This rule aims to identify potential compromise attempts or active infections involving remote access tools often abused by adversaries.
avatar
Aamir Muhammad@Aamir
avatar
Detections.ai Community
1 year ago
51106
This query is designed to detect a series of anomalous user behaviors that, when combined, may indicate a compromised account. It flags activity that is uncharacteristic for a specific user, such as performing an unusual action, using an unfamiliar application, connecting from an unexpected ISP or country, or logging in from a new device for the first time. The final filter | where InvestigationPriority > 5 focuses the results on high-priority alerts, which are more likely to be legitimate threats. This approach uses behavioral analytics to identify deviations from a user's normal baseline, making it effective for detecting both insider threats and external attacks that have breached credentials.
avatar
Benjamin Zulliger@benscha
avatar
Detections.ai Community
1 year ago
211276
Detects indicators associated with a supply chain attack compromising popular NPM packages like 'chalk' and 'debug'. The rule identifies network connections to known malicious domains and command-line activity related to the installation of compromised packages.
avatar
Varshil D.@VQL
avatar
Detections.ai Community
1 year ago
152339
This rule identifies statistically unusual or first-time Azure operations performed by a principal (user or service principal). It uses a risk-based alerting model, assigning a higher risk score to operations defined as high-risk. The rule establishes a baseline of normal activity over 30 days and alerts when current activity significantly deviates from this baseline or when an operation is observed for the very first time for a given identity.
Kyle Barboza@azobrab
avatar
Detections.ai Community
1 year ago
41247
Detects potential Adversary-in-the-Middle (AiTM) phishing activity, commonly associated with frameworks like Evilginx. The rule identifies suspicious domain patterns where legitimate identity provider (IdP) domains are used as subdomains of another domain, or where IdP-related keywords are used in hyphenated subdomains.
avatar
Tim Peck@timpeck
avatar
Detections.ai Community
1 year ago
50184
Detects a sequence of file creations (.svg, .zip, .bat) on a single host within a short time window, which is indicative of a malicious SVG-based download campaign delivering payloads like XWorm and Remcos.
avatar
Tim Peck@timpeck
avatar
Detections.ai Community
1 year ago
4285
This rule detects attempts to download known malicious NPM packages from the public npm registry (registry.npmjs.org) by monitoring network connection logs. It specifically looks for tarball (.tgz) downloads of packages and versions that have been identified as compromised or malicious. The rule extracts the package name and version from the download URL and compares it against a predefined list of malicious packages for high-fidelity detection.
avatar
Arnold Chan@slaz
avatar
Detections.ai Community
1 year ago
32210
Detects the presence of specific compromised versions of popular NPM packages. These versions were tampered with to include a malicious crypto wallet drainer as part of a supply chain attack.
avatar
Elgonad .@elgonad
avatar
Detections.ai Community
1 year ago
00114
Page 163 of 235