Password-Protected RAR Smuggling APT28's HOOKEDGE Stager Past Perimeter AV

In the 2026-08-28 CISO Daily Digest, Russia-linked APT28 (Fancy Bear) was tied to the HOOKEDGE backdoor actively targeting European government and diplomatic entities for espionage, riding the group's standard playbook of diplomatic/foreign-ministry phishing and credential abuse. A recurring APT28 tradecraft for getting a stager onto a victim host without tripping signature scanners is to wrap the payload in a password-protected archive: the attacker emails a .rar or .zip encrypted with a known password (often disclosed in the message body), so the inner file's content is opaque to any control that only inspects the outer container. Because the encrypted bytes never match a malware hash and the real stager is invisible until decrypted, naive perimeter AV and single-pass mail gateways let it through. This demo reproduces the evasion shape safely — the inner payload is a benign RAR-protected marker (no executable code, no macro, no calculator, no network), password 'infected', so there is zero real payload and no destruction. MetaDefender Archive Engine recursively unpacks and, where policy permits, de-protects archives across every layer, applies deep multi-engine scanning to each extracted file, and surfaces the concealed content — so password-shrouded stagers like the HOOKEDGE loader behind the APT28 diplomatic-phishing chain cannot slip past undetected.