https://locodigital.com.br/en/tags/hackers/Recent content in Hackers on LocodigitalHugoen-USSat, 12 Sep 2026 09:00:00 -0300https://locodigital.com.br/en/technology/yahoo-breach-2013-the-biggest-leak-in-history/Sat, 12 Sep 2026 09:00:00 -0300https://locodigital.com.br/en/technology/yahoo-breach-2013-the-biggest-leak-in-history/<p>In August 2013, someone broke into Yahoo's servers and copied the data of every user registered with the service. Three years later the company still did not know — or at least that is what it told the world. When the truth finally came out, in October 2017, the final number was staggering: <strong>3 billion accounts compromised</strong>. To this day it remains the largest publicly confirmed data breach ever.</p> <h2>How the intrusion happened</h2> <p>The 2013 attack exploited Yahoo's internal authentication system. Rather than stealing passwords — which would have meant cracking them one by one — the intruders <strong>forged session cookies</strong>. A session cookie is the file your browser keeps after you log in; it is what tells the site "this one already authenticated, let them through". With access to the server keys, you can mint a fake cookie that Yahoo accepted as legitimate.</p>