21CTO

Apr 30, 2016 · Information Security

How to Bypass PHP 7 OPcache File Restrictions with a Binary Webshell

This article explains the security flaws in PHP 7's OPcache engine, demonstrates a novel binary webshell attack that bypasses file‑write protections, and provides step‑by‑step exploitation techniques including file‑cache manipulation, memory‑cache bypass, and timestamp spoofing.