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XBOW: A Shell Is Worth a Thousand Images

XBOW's autonomous AI agent chained a blind SSRF in Bing's reverse-image-search into three Critical Microsoft RCEs (CVE-2026-32194, CVE-2026-32191, CVE-2026-21536), each CVSS 9.8, by fingerprinting an ImageMagick-compatible backend through differential error responses and crafting an SVG payload that reached a shell-backed image delegate. The proof was confirmed via out-of-band callbacks showing NT AUTHORITY\SYSTEM and root execution across multiple production Bing image-processing workers on both Windows and Linux hosts. The piece walks through the full investigative trace — from ruling out XXE to fingerprinting ImageMagick coders/pseudo-protocols to constructing the pipe-based SVG exploit — and argues that ImageTragick-class bugs in "boring" image helpers remain a live, underrated attack surface.