Is it safe to add anyone on steam?

After I made a long closed down thread on backpack.tf regarding several unusuals, this dodgy russian guy has kept trying to add me on steam. He makes a new private alt every day in an attempt to get me to add him (this is his latest: http://steamcommunity.com/id/aliden1990) and I was wondering what the risks are of adding him. I've heard that through the use of certain programs your ip can be detected when a voice chat is initiated, but I was wondering if there are any risks to simply accepting a friend request, as I'd quite like to berate the bastard since steam support haven't responded to my requests for help and I am getting sick of this pricks persistence. Thanks.

adding one to friends is not a real risk. Now, the chatting, thats where one should pay attention, for phishing links etc.

A good tip on such is to give everybody a nickname in steam. That will always be shown along their name in the chat box or in the friends list for you, or on their profiles. You can use that to add reminders to ppl of what/whom they are.

As for finding your IP, as long as you are behind a router, and have a decent antivirus with a firewall (not of the Microsoft variety), they cannot do any with that.

This prick is stills ending me friend requests and its getting really annoying. (latest alt: http://steamcommunity.com/id/helgaolha21/) Is there anything I can actually do to stop this or do I just have to wait it out?

You can simply block/not accept people who add you until this stops. If you are certain it's him on an alt, you can report him on his steam profile. I'm pretty sure its labeled as harassment or spamming invites.

but, can you know who is the lastest friend i add? cause i'm share my account with my friend

That's a terrible idea, for a few reasons. What if your "friend" does some sort of scam on your account? Or if someone he adds tries to talk to you while you have control of the account and thinks that the account is hijacked?

I'd tell your friend to get his own account.

indeed, tell the friend to get his own account, or you yourself to get your own account.

Adding anyone on steam is never a threat in my opinion, transactions, trades, conversations are what matter the most

It's NOT safe to add random people to your friends list, since adding someone allows that person to know your IP address through a chat bug.

1. They don't need to have you added to chat with you.
2. The "chat bug" to get one's IP, great, but a IP isn't really any one can use unless they want to DDOS them.

To attack their computer, that is a different angle, they will have to get that person to install something, or visit a site that hacks their browser. As long as you have a good antivirus, firewall (and no, Microsoft stuff does NOT count for that) and a router, you wont get a problem from any having your IP.

A example:
- Set in your router to use Open DNS: http://www.opendns.com/ (make a account, and you can control what type of sites get passed thru)
- MVPS Hosts: http://winhelp2002.mvps.org/hosts.htm (auto updated with HostsMan: http://www.abelhadigital.com/hostsman )
- SpywareBlaster: https://www.brightfort.com/spywareblaster.html (Protects your browser(s)
- Spybot S&D: http://www.safer-networking.org/dl/ (imunize & real time protection)
- Disable DNS Client service of windows (all versions): http://support.simpledns.com/kb/a61/disabling-the-windows-dns-client-service.aspx (reason is that this service is often attacked by various malware)
- ESET Smart Security (paid, Anti-virus, anti-spyware & firewall): http://www.eset.com/int/

And then for the browser use for example Firefox:
- Adblock Plus: https://addons.mozilla.org/en-US/firefox/addon/adblock-plus/?src=search
- Element Hiding Helper for Adblock Plus : https://addons.mozilla.org/en-US/firefox/addon/elemhidehelper/?src=search
- NoScript: https://addons.mozilla.org/en-US/firefox/addon/noscript/?src=search

And for SR in Firefox:
- GreaseMonkey: https://addons.mozilla.org/en-US/firefox/addon/greasemonkey/?src=search
- GreaseMonkey Script (Steamrep Profile checker) : http://userscripts.org/scripts/show/169705 (Made by "n0:name" of FoG)

There are somewhat equivalent plugins for chrome, but I never sorted those out. IE... well, lets just say its the browser where you often cannot remove bad plugins from within the browser, and sorting that out manually isn't for most ppl. While the same is pretty easy in FF.

With the above, I never see ads, and almost all "dangerous" sites are blocked. OpenDNS has a feature that with mistyping URL's you get redirected to the real one etc (to not get on typesquatting sites). On computers I maintain I install above as well, but they sometimes do not want a paid antivirus, so I then install Avast Free. All the other stuff is free. And most is not running along with your computer, or is very minimal usage.

Then a final thing. people think somehow that having a VPN or Proxy is a "safety feature" while those VPN's and proxy's are often set up by parties you do not know, and can be harmful for you, for they can operate MiM attacks, track your browsing etc. Even TOR isn't as safe as ppl think. Its already proven that somebody can run a gateway and find all kinds of stuff about its users. For ppl start using that for EVERYTHING... including their browsing of sites like facebook etc. and by your browsing behavior you are traceable as a unique user.

So while somebody having your IP is all nice and dandy, there is no real danger to that. The real danger is you, you giving out the information they want, like login names, passwords, email addresses, steam guard codes, personal details which hijackers can use to gain foothold on steam support. Or ignorance in maintaining security of your computer. Sure, its impossible to 100% secure your computer. But the real defense of your computer is sitting behind the keyboard in the end. The user can in the end check the computer with process explorer etc, send suspicious files to the antivirus maker etc.

I still hear of ppl not running a antivirus program "for they do not encounter virusses, and they are in full control of the PC"...

For me that constitutes not being safe.

I don't need to be friends or w/e on steam with someone to get their IP, and yes, that is without all my various accesses granted to me by/for SR.

Point being, as soon as you connect to anything, be that a website, a game server, or some other service, somebody knows your IP. Linking the dots is after that is easy.

If you do not feel "secure" with people able to get your IP, then the only way to prevent people to get an IP is unplug your router, cut your internet connection and be done with it. There is no other way of preventing it, and as I stated above, using proxies/vpn's is even less safe in usage.

But you know that, you're a programmer, Fernando.