Abusing Application Layer Gateways (NAT Slipstreaming)
infonews
security
Source: Embrace The RedNovember 24, 2020
Summary
NAT Slipstreaming is a technique where visiting a malicious website can punch a hole through your router's firewall by exploiting the Application Layer Gateway (ALG, a feature that helps protocols like SIP, Session Initiation Protocol, work with firewalls). The attack works because the ALG is designed to allow devices inside a network to open firewall ports, but an attacker can abuse this intended functionality.
Classification
Attack SophisticationModerate
Original source: https://embracethered.com/blog/posts/2020/nat-slipstreaming-simplified/
First tracked: February 12, 2026 at 02:20 PM
Classified by LLM (prompt v3) · confidence: 95%