hdchinh hdchinh

hi, i'm daniel. i'm a 15-year-old high school junior. in my free time, i hack billion dollar companies and build cool stuff.

3 months ago, I discovered a unique 0-click deanonymization attack that allows an attacker to grab the location of any target within a 250 mile radius. With a vulnerable app installed on a target's phone (or as a background application on their laptop), an attacker can send a malicious payload and deanonymize you within seconds--and you wouldn't even know.

I'm publishing this writeup and research as a warning, especially for journalists, activists, and hackers, about this type of undetectable attack. Hundreds of applications are vulnerable, including some of the most popular apps in the world: Signal, Discord, Twitter/X, and others. Here's how it works:

Cloudflare

By the numbers, Cloudflare is easily the most popular CDN on the market. It beats out competitors such as Sucuri, Amazon CloudFront, Akamai, and Fastly. In 2019, a major Cloudflare outage k

	1. Gemfile

	gem 'ckeditor', github: 'galetahub/ckeditor'

	2. bundle install

	3. app/assets/javascripts/application.js
	//= require ckeditor/init

	4. config/initializers/active_admin.rb

	require "prawn"

	class AddWatermarkService
	def initialize(cv)
	@cv = cv
	end

	def perform
	begin
	return { cv: @cv, success: false } if File.extname(@cv.original_filename) != ".pdf"