The research of Yang Yu, founder of Tencent’s Xuanwu Lab, has helped Microsoft patch a severe security issue in its implementation of the NetBIOS protocol that affected all Windows versions ever released.

Yu says an attacker could leverage this vulnerability to pass as a WPAD or ISATAP server and redirect all the victim’s network traffic through a point controlled by the attacker.

By network traffic, Yu refers to all traffic, not just Web HTTP and HTTPS. This includes OS updates, software upgrades, Certificate Revocation List updates via Microsoft’s Crypto API, and other OS maintenance operations.

Source: BadTunnel Bug Hijacks Network Traffic, Affects All Windows Versions