{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/internet-information-services-iis/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Nginx","Apache HTTP Server","Apache Tomcat","Internet Information Services (IIS)","Traefik"],"_cs_severities":["low"],"_cs_tags":[],"_cs_type":"advisory","_cs_vendors":["Apache Software Foundation","Microsoft","Traefik Labs","Nginx"],"content_html":"\u003cp\u003eRemote File Inclusion (RFI) is a web application vulnerability where an application improperly handles user-supplied input, allowing an attacker to coerce the server into including or executing files from remote resources. By manipulating URL parameters, attackers can bypass security controls to read local configuration files, probe system information, or download secondary malicious payloads for command-and-control (C2) or persistence.\u003c/p\u003e\n\u003cp\u003eDefenders must differentiate between malicious activity and legitimate application functionality, such as content proxies, feed importers, or diagnostic tools that legitimately accept URLs as parameters. Given the high noise associated with these patterns, security teams should focus on correlating ingress HTTP GET requests that result in a 200 OK status with subsequent anomalous outbound network connections from the web server. This brief provides a framework for detecting and investigating such activity across common web server platforms including Nginx, Apache, and IIS.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker performs reconnaissance to identify endpoints accepting URL parameters (e.g., ?page= or ?url=).\u003c/li\u003e\n\u003cli\u003eAttacker probes the endpoint with various URI schemes like http://, file://, or php:// to test if the server resolves the resource.\u003c/li\u003e\n\u003cli\u003eAttacker sends a malicious HTTP GET request containing an external URL or IP address in a vulnerable query parameter.\u003c/li\u003e\n\u003cli\u003eThe web server application processes the parameter and makes an outbound request to the attacker-controlled resource.\u003c/li\u003e\n\u003cli\u003eThe attacker's server delivers a malicious payload (e.g., a web shell or script) or triggers a local file inclusion for data exfiltration.\u003c/li\u003e\n\u003cli\u003eThe web server executes or includes the fetched content, establishing a foothold or disclosing server-side configuration data.\u003c/li\u003e\n\u003cli\u003eAttacker establishes C2 via the newly deployed script or uses the access to perform further internal discovery.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful RFI exploitation enables unauthorized remote code execution, sensitive data exposure (e.g., .env or config.php files), and the deployment of persistent threats within the internal network. Organizations may face full application compromise and significant data theft depending on the sensitivity of the exposed server files.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cp\u003ePrioritize the implementation of traffic monitoring and hardening to mitigate RFI risks.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eImplement strict input validation and normalization for all user-supplied query parameters.\u003c/li\u003e\n\u003cli\u003eDisable risky features in application configurations, such as setting PHP \u003ccode\u003eallow_url_include\u003c/code\u003e and \u003ccode\u003eallow_url_fopen\u003c/code\u003e to \u003ccode\u003eOff\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eEnforce \u003ccode\u003eopen_basedir\u003c/code\u003e restrictions to limit the file system access available to web applications.\u003c/li\u003e\n\u003cli\u003eMonitor for anomalous outbound connections from web server hosts using egress firewall or proxy logs.\u003c/li\u003e\n\u003cli\u003eInspect webroot and temporary directories (e.g., /tmp, /var/www) for unauthorized file creation or script modifications following alerts.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-09-18T19:14:11Z","date_published":"2026-09-18T19:14:11Z","id":"https://feed.craftedsignal.io/briefs/2026-09-web-server-rfi-activity/","summary":"This brief outlines the identification and response strategy for Remote File Inclusion (RFI) attacks, where adversaries exploit web server vulnerabilities to fetch remote payloads or disclose sensitive local files.","title":"Detection of Potential Remote File Inclusion (RFI) Activity","url":"https://feed.craftedsignal.io/briefs/2026-09-web-server-rfi-activity/"}],"language":"en","title":"CraftedSignal Threat Feed - Internet Information Services (IIS)","version":"https://jsonfeed.org/version/1.1"}