I once found a hidden door in a fortress. It wasn’t meant to be there. Today, I’ll show you how a tiny timing issue, known as a Race Condition Vulnerability, can be the key to a major security flaw.

Why should you care?
If you use two-factor authentication (2FA) to protect your accounts, you trust it to be a solid wall.

This story matters because it demonstrates how that wall can sometimes have a secret passage.

Understanding these flaws is how we make the digital world safer for everyone.

When Two Requests Have a Race

The main concept is surprisingly simple. Imagine two lines at a coffee shop, both leading to the same barista.

1. You get in the first line and hand over your loyalty card to get a stamp (this is like starting the 2FA login process).
2. Very quickly, you jump into the second line before the barista has finished stamping your card.
3. You ask for a free coffee (this is like asking to access your account).
4. If the barista is too busy and just hands you the coffee without checking if the stamping in the first line is done, you’ve won the race.