Description

Researchers published a proof-of-concept called Brash that exploits an architectural flaw in Chromium’s Blink rendering engine. By performing unconstrained, high-frequency updates to document.title, the PoC forces Chromium-based browsers to allocate massive amounts of memory and saturate the main thread, producing a denial-of-service (tab/browser crash) in seconds (tests report up to ~18 GB RAM consumption). The authors published the exploit and tooling after disclosure attempts. The root cause is the absence of rate-limiting/throttling on document.title updates inside Blink. The PoC preloads large, high-entropy strings then issues configurable “bursts” of title writes (millions of updates per second by default). Each synchronous document.title assignment is processed on the browser’s main/UI thread; when bombarded, it blocks the event loop, thrashes the compositor, drives CPU use and memory growth, and prevents user interaction or graceful shutdown. Timelines in testing show UI freeze within a few seconds and forced termination required within 15–60s depending on browser and platform. All major Chromium derivatives tested (Chrome, Edge, Brave, Arc, Opera, etc.) are shown vulnerable; engines not based on Blink (Firefox/Gecko, Safari/WebKit) are not affected. The repo lists affected Chromium builds (tested up to and including 143.0.7483.0) and provides demos and config knobs for burst size and interval for reproducibility.