WebDAV

Cybercriminals are exploiting a legacy feature in Windows File Explorer, specifically the WebDAV protocol, to distribute malware and bypass traditional security measures. Despite Microsoft deprecating native WebDAV support in November 2023, it remains active on many systems. Attackers use WebDAV to deceive victims into executing malicious payloads by sending links that connect File Explorer directly to remote servers, avoiding web browsers and their security warnings. They employ methods such as direct linking, URL shortcut files, and LNK shortcut files to deliver exploits. The primary objective of these campaigns, which surged in late 2024, is to deploy Remote Access Trojans (RATs), with 87% of Active Threat Reports involving multiple RATs like XWorm RAT, Async RAT, and DcRAT. These campaigns predominantly target corporate networks in Europe, with many phishing emails written in German and English. Attackers use short-lived WebDAV servers hosted on Cloudflare Tunnel demo accounts to obscure their infrastructure. Security analysts are advised to monitor unusual network activity from Windows Explorer and educate users to verify addresses in File Explorer.