{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/download/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":["FIN7","Carbon Spider","Sangria Tempest"],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["curl","download","file-sharing","ingress-tool-transfer","windows","threat-hunting"],"_cs_type":"threat","_cs_vendors":[],"content_html":"\u003cp\u003eThreat actors, including sophisticated groups like FIN7, are known to leverage legitimate system utilities such as \u003ccode\u003ecurl.exe\u003c/code\u003e to download secondary stage payloads or malicious tools onto compromised Windows machines. This technique involves using \u003ccode\u003ecurl.exe\u003c/code\u003e to connect to publicly accessible, but often abused, file-sharing services and CDNs (e.g., \u003ccode\u003egithubusercontent.com\u003c/code\u003e, \u003ccode\u003emega.nz\u003c/code\u003e, \u003ccode\u003ecdn.discordapp.com\u003c/code\u003e) to retrieve executable binaries, scripts (\u003ccode\u003e.ps1\u003c/code\u003e, \u003ccode\u003e.bat\u003c/code\u003e), or dynamic link libraries (\u003ccode\u003e.dll\u003c/code\u003e). The activity is characterized by \u003ccode\u003ecurl.exe\u003c/code\u003e command-line arguments specifying a download operation (e.g., \u003ccode\u003e-O\u003c/code\u003e, \u003ccode\u003e--remote-name\u003c/code\u003e, \u003ccode\u003e--output\u003c/code\u003e) and targeting specific file extensions. This method allows adversaries to bypass traditional perimeter defenses and introduce hostile code into a network, establishing persistence, escalating privileges, or preparing for data exfiltration and ransomware deployment. This behavior was highlighted in a detection rule originally published in May 2023 and updated in March 2026.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003e\u003cstrong\u003eInitial Access\u003c/strong\u003e: An attacker gains initial access to a Windows system, possibly through spearphishing, exploiting a vulnerable service, or compromised credentials.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eExecution of Initial Command\u003c/strong\u003e: The attacker establishes a foothold and executes an initial command-and-control mechanism or interactive shell (e.g., PowerShell, cmd.exe).\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eIngress Tool Transfer\u003c/strong\u003e: \u003ccode\u003ecurl.exe\u003c/code\u003e is launched from the command line with parameters to download additional malicious tools or payloads from an external source.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eSuspicious Download\u003c/strong\u003e: \u003ccode\u003ecurl.exe\u003c/code\u003e connects to a public file-sharing or content delivery network (CDN) domain (e.g., \u003ccode\u003egithubusercontent.com\u003c/code\u003e, \u003ccode\u003emega.nz\u003c/code\u003e, \u003ccode\u003ecdn.discordapp.com\u003c/code\u003e) to retrieve a file.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003ePayload Staging\u003c/strong\u003e: The malicious file (e.g., \u003ccode\u003e.exe\u003c/code\u003e, \u003ccode\u003e.ps1\u003c/code\u003e, \u003ccode\u003e.dll\u003c/code\u003e, \u003ccode\u003e.msi\u003c/code\u003e) is saved to a specific location on the compromised system, often a temporary directory or a less scrutinized path.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eSecondary Payload Execution\u003c/strong\u003e: The downloaded malicious payload is executed, leading to further compromise, such as establishing persistence, escalating privileges, deploying ransomware, or exfiltrating data.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation results in the introduction and execution of arbitrary malicious code on the compromised system. This can lead to severe consequences including, but not limited to, full system compromise, data exfiltration, deployment of ransomware, establishment of persistent backdoors for long-term access, and lateral movement within the network. The specific impact depends on the nature of the downloaded payload, but the use of legitimate tools like \u003ccode\u003ecurl.exe\u003c/code\u003e increases the likelihood of unnoticed initial compromise and enables sophisticated post-exploitation activities, potentially affecting multiple systems across an organization.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026quot;Suspicious File Download From File Sharing Domain Via Curl.EXE\u0026quot; to your SIEM and tune for your environment to detect \u003ccode\u003ecurl.exe\u003c/code\u003e activity.\u003c/li\u003e\n\u003cli\u003eEnable comprehensive process creation logging (e.g., via Sysmon) to ensure visibility into \u003ccode\u003ecurl.exe\u003c/code\u003e executions and their command-line arguments.\u003c/li\u003e\n\u003cli\u003eReview network egress logs for connections to the file-sharing domains listed in the IOC section, especially when initiated by non-standard processes.\u003c/li\u003e\n\u003cli\u003eImplement application control policies to restrict unauthorized execution of \u003ccode\u003ecurl.exe\u003c/code\u003e or its use to download specific file types from untrusted sources.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-07-03T15:10:57Z","date_published":"2026-07-03T15:10:57Z","id":"https://feed.craftedsignal.io/briefs/2026-07-suspicious-curl-download/","summary":"A high-severity threat involves the abuse of `curl.exe` on Windows systems to download potentially malicious files from various public file-sharing and content delivery network (CDN) domains, a technique observed in campaigns by threat actors such as FIN7, leading to further system compromise.","title":"Suspicious File Download From File Sharing Domain Via Curl.EXE","url":"https://feed.craftedsignal.io/briefs/2026-07-suspicious-curl-download/"}],"language":"en","title":"CraftedSignal Threat Feed - Download","version":"https://jsonfeed.org/version/1.1"}