{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/crackmapexec/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["netexec","crackmapexec","lateral-movement","post-exploitation","hacktool"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eNetExec (formerly CrackMapExec) is a widely used post-exploitation tool favored by penetration testers and malicious actors for Active Directory enumeration, credential harvesting, and remote code execution. When executed on a Windows system, NetExec extracts its embedded data files into a temporary directory named \u0026ldquo;_MEI\u0026rdquo; followed by a random string, located under the user\u0026rsquo;s Temp folder. A specific subdirectory, \u0026ldquo;\\nxc\\data\u0026quot;, within this extraction path contains files unique to NetExec. These file creation events offer a reliable indicator for detecting NetExec execution on a host. This activity is important for defenders as it signals potential reconnaissance, lateral movement attempts, or the establishment of a foothold within the network.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker gains initial access to a system through various means (e.g., compromised credentials, exploiting a vulnerability).\u003c/li\u003e\n\u003cli\u003eThe attacker uploads the NetExec executable (nxc.exe) to the compromised host.\u003c/li\u003e\n\u003cli\u003eThe attacker executes nxc.exe.\u003c/li\u003e\n\u003cli\u003eNetExec extracts its embedded data files into a temporary directory. The path follows the pattern: \u003ccode\u003e\\Temp\\_MEI\u0026lt;random\u0026gt;\\\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eWithin the temporary directory, a specific subdirectory \u003ccode\u003e\\nxc\\data\\\u003c/code\u003e is created, containing NetExec\u0026rsquo;s data files.\u003c/li\u003e\n\u003cli\u003eNetExec utilizes these files for Active Directory enumeration, credential harvesting, and reconnaissance activities.\u003c/li\u003e\n\u003cli\u003eThe attacker leverages gathered information to move laterally within the network, potentially targeting other systems or services.\u003c/li\u003e\n\u003cli\u003eThe attacker may attempt to execute code remotely using harvested credentials, furthering their access and control within the environment.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful NetExec deployment can lead to extensive reconnaissance of Active Directory environments, enabling attackers to map out network infrastructure, identify valuable targets, and harvest credentials. This can result in unauthorized access to sensitive data, lateral movement to critical systems, and ultimately, a complete compromise of the domain. Organizations in all sectors are vulnerable, with the impact ranging from data breaches and financial loss to reputational damage and operational disruption.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the provided Sigma rule \u003ccode\u003eDetect NetExec File Creation\u003c/code\u003e to your SIEM to detect NetExec\u0026rsquo;s unique file creation patterns (logsource: file_event, product: windows).\u003c/li\u003e\n\u003cli\u003eMonitor file creation events in the \u003ccode\u003e\\Temp\u003c/code\u003e directory for filenames containing \u003ccode\u003e_MEI\u003c/code\u003e and \u003ccode\u003e\\nxc\\data\\\u003c/code\u003e, as these indicate NetExec\u0026rsquo;s extraction process.\u003c/li\u003e\n\u003cli\u003eEnable process-creation logging with command-line arguments to identify the execution of \u003ccode\u003enxc.exe\u003c/code\u003e (logsource: process_creation, product: windows).\u003c/li\u003e\n\u003cli\u003eInvestigate any alerts generated by these rules to determine the extent of the compromise and contain any further lateral movement.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-18T12:00:00Z","date_published":"2024-01-18T12:00:00Z","id":"/briefs/2024-01-netexec-file-indicators/","summary":"This brief covers the detection of NetExec, a post-exploitation and lateral movement tool, through monitoring for unique file creation patterns associated with its execution and file extraction in Windows environments.","title":"NetExec File Creation Detection","url":"https://feed.craftedsignal.io/briefs/2024-01-netexec-file-indicators/"}],"language":"en","title":"CraftedSignal Threat Feed — Crackmapexec","version":"https://jsonfeed.org/version/1.1"}