{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/castleloader/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Microsoft Windows","Microsoft 365","Google Workspace"],"_cs_severities":["high"],"_cs_tags":["clickfix","malware","social-engineering","rat","infostealer","castleloader","netsupport"],"_cs_type":"advisory","_cs_vendors":["Microsoft"],"content_html":"\u003cp\u003eThe BackgroundFix campaign is a social engineering scheme using fake \u0026ldquo;remove your photo background\u0026rdquo; services to deliver malware. Victims are lured to malicious sites mimicking legitimate image editing tools. The sites feature fake upload interfaces, progress bars, and download buttons to appear authentic. This campaign delivers a multi-stage payload, starting with CastleLoader. CastleLoader then drops NetSupport RAT, enabling remote access for the attackers, and CastleStealer, a custom .NET stealer designed to exfiltrate browser credentials, wallet extension data, and Telegram session files. This campaign appears to be active, with multiple domains sharing the same template.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eVictim searches for an online background removal tool and lands on a malicious BackgroundFix site.\u003c/li\u003e\n\u003cli\u003eThe victim uploads an image to the fake website.\u003c/li\u003e\n\u003cli\u003eAfter clicking a checkbox, the site instructs the victim to copy a command to their clipboard.\u003c/li\u003e\n\u003cli\u003eThe copied command executes \u003ccode\u003efinger.exe\u003c/code\u003e to query \u003ccode\u003echeeshomireciple[.]com\u003c/code\u003e\u003c/li\u003e\n\u003cli\u003e\u003ccode\u003efinger.exe\u003c/code\u003e retrieves a batch script from the C2 server.\u003c/li\u003e\n\u003cli\u003eThe batch script executes commands to download and execute further payloads.\u003c/li\u003e\n\u003cli\u003eCastleLoader is deployed, subsequently dropping NetSupport RAT and CastleStealer.\u003c/li\u003e\n\u003cli\u003eNetSupport RAT grants the attacker remote access, while CastleStealer exfiltrates sensitive data.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful attacks result in the installation of NetSupport RAT, granting attackers remote control over the compromised system. Additionally, CastleStealer exfiltrates sensitive information such as browser credentials, wallet extension data, and Telegram session files. This stolen data can be used for further malicious activities, including financial fraud, identity theft, and unauthorized access to sensitive accounts. The active nature of the campaign and the use of multiple domains suggest a broad targeting scope.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eMonitor process creation events for the execution of \u003ccode\u003efinger.exe\u003c/code\u003e with command-line arguments pointing to external domains (IOC: \u003ccode\u003echeeshomireciple[.]com\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule to detect the execution of \u003ccode\u003efinger.exe\u003c/code\u003e to identify potential initial access attempts.\u003c/li\u003e\n\u003cli\u003eBlock the C2 domain \u003ccode\u003echeeshomireciple[.]com\u003c/code\u003e at the DNS resolver to prevent initial payload delivery.\u003c/li\u003e\n\u003cli\u003eMonitor network connections for NetSupport RAT C2 communications on port 688 to detect compromised systems (IOCs: \u003ccode\u003eporonto[.]com:688\u003c/code\u003e, \u003ccode\u003egiovettiadv[.]com:688\u003c/code\u003e).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-30T13:00:00Z","date_published":"2026-04-30T13:00:00Z","id":"/briefs/2026-04-clickfix-backgroundfix/","summary":"The 'BackgroundFix' ClickFix campaign uses social engineering to trick victims into downloading malware disguised as a free image-editing tool, leading to the deployment of CastleLoader, NetSupport RAT for remote access, and CastleStealer for credential theft.","title":"ClickFix 'BackgroundFix' Campaign Delivers CastleLoader, NetSupport RAT, and CastleStealer","url":"https://feed.craftedsignal.io/briefs/2026-04-clickfix-backgroundfix/"}],"language":"en","title":"CraftedSignal Threat Feed — Castleloader","version":"https://jsonfeed.org/version/1.1"}