Steam may have security vulnerabilities and have been exploited by hackers.

[SWTO]

There may be security vulnerabilities in steam, which leads hackers to bypass the protection of the security order application and steal some properties in the account, even if the steam account is within the scope of safe use.
Because I have experienced it, I sorted it out and made some speculation. However, due to the safety issues and laws involved, its feasibility cannot be verified.
I don't know whether this issue is suitable for public discussion, but steam customer service suggested that I come here to talk about it.
I have some evidence to prove the possibility of this vulnerability, but I think it is really not suitable for public discussion.

[Mad Scientist]

I believe this is the place to use if you believe there's a vulnerability:

https://hackerone.com/valve?type=team

Support always redirects things they aren't involved with as "post on the forums"

The provided link is to actually communicate with and reward a user that finds an actual exploit. If found to be true, they'll likely be in touch.

[SWTO]

Mad Scientist님이 먼저 게시:

I believe this is the place to use if you believe there's a vulnerability:

https://hackerone.com/valve?type=team

Support always redirects things they aren't involved with as "post on the forums"

The provided link is to actually communicate with and reward a user that finds an actual exploit. If found to be true, they'll likely be in touch.

Thank you for your reply, but I don't trust the third-party organizations very much. I prefer to solve the problem within steam. If it really can't be solved, go to seek their help.
Compared with the bonus, I care more about the security of my account. After all, here is my happy memory of playing games for a long time.
Thank you again for providing me with another channel. I will remember it. thank you.

[Aachen]

That’s affiliated with Valve; see https://www.valvesoftware.com/en/security/

[Bee🐝]

SWTO님이 먼저 게시:

Mad Scientist님이 먼저 게시:

I believe this is the place to use if you believe there's a vulnerability:

https://hackerone.com/valve?type=team

Support always redirects things they aren't involved with as "post on the forums"

The provided link is to actually communicate with and reward a user that finds an actual exploit. If found to be true, they'll likely be in touch.

Thank you for your reply, but I don't trust the third-party organizations very much. I prefer to solve the problem within steam. If it really can't be solved, go to seek their help.
Compared with the bonus, I care more about the security of my account. After all, here is my happy memory of playing games for a long time.
Thank you again for providing me with another channel. I will remember it. thank you.

Mad gave you the best possible way to go about this.

You can’t actually state what the exploit is in the open forums, so there’s not really anything anyone can weight in on.

Report it and then see what happens.

[Satoru]

SWTO님이 먼저 게시:

Mad Scientist님이 먼저 게시:

I believe this is the place to use if you believe there's a vulnerability:

https://hackerone.com/valve?type=team

Support always redirects things they aren't involved with as "post on the forums"

The provided link is to actually communicate with and reward a user that finds an actual exploit. If found to be true, they'll likely be in touch.

Thank you for your reply, but I don't trust the third-party organizations very much. I prefer to solve the problem within steam. If it really can't be solved, go to seek their help.
Compared with the bonus, I care more about the security of my account. After all, here is my happy memory of playing games for a long time.
Thank you again for providing me with another channel. I will remember it. thank you.

The fact that you don't know who HackerOne is sort of says a lot of this 'exploit' you purport to have

[rawWwRrr]

SWTO님이 먼저 게시:

There may be security vulnerabilities in steam, which leads hackers to bypass the protection of the security order application and steal some properties in the account

There certainly is. They are the naive users who quickly give away their login details on the promise of a quick profit.

[B-o-B]

If "hackers" have an exploit of some kind then why did they target little old you and not someone with much more expensive account/items?

Here's the best security tip ever: Don't sign into anything 3'rd party, with your Steam Account.
Problem solved.
There is No Exploits.

[SWTO]

Aachen님이 먼저 게시:

That’s affiliated with Valve; see https://www.valvesoftware.com/en/security/

Thank you. It's very useful.