Your CS2 skins live on your Steam account, not in the game. If someone gets into that account, they can move your inventory out before you notice. Steam's answer to that is Steam Guard, and the version that actually protects a valuable inventory is the Mobile Authenticator.
What the Mobile Authenticator does
The Mobile Authenticator is part of the Steam Mobile App. It generates a code that you enter every time you sign in. The code changes every 30 seconds, can be used once, and cannot be guessed. On its own that is stronger than a username and password. The app also supports QR code sign in, which skips the username and password step entirely.
How to set it up
- Sign in to the Steam Mobile App. You land on the Steam Guard tab, where you select Add authenticator.
- Enter a phone number Steam can confirm by text message. If you lose access to your account later, that number is how you recover it. VoIP numbers are not accepted.
- Enter the confirmation code Steam sends you.
- Write down the recovery code Steam shows you. This code lets you recover your account yourself if you lose your phone or the authenticator. Keep it somewhere safe.
What it means for your trades and listings
Trades and Market listings created before you add the authenticator, or during the first seven days after you add it, are held for 15 days. Listings created more than seven days after the authenticator is added are not held. Adding the authenticator does not shorten holds that already exist.
If your account is taken
Do not share your authenticator codes with anyone, and do not type them into a site that is not run by Valve. Steam Support will never ask for your password or your authenticator code. If you lose your phone, the recovery code from setup is what gets you back in, so losing that code is the real problem.
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