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Windows (in this case XP) allows me to simply "share a folder" via its SMB protocol, and I can access it via Linux quite nicely (with Samba), no questions asked.

That's what bothers me, it just does not feel secure, and the "security" section of the Wikipedia page is discouraging. I love being able to just tell Windows to share a folder and imediately have these personal files on the Linux box (and with R/W access), but I don't want these files to be deletable or even accessible from the internet. I'm not even being asked a password! Can people all over the world access my shared folders without a password too?

The topography is: One machine Windows XP SP3, the other Linux Mint Debian edition, and both connected to the internet (and to each other) via a router that my ISP gave me. It has WPA-encrypted Wi-FI, but I connect these two via LAN cable.

Am I secure in my usage of Windows' file sharing (maybe by being behind a router)? Do I have to do something?

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A properly configured router with a built in firewall and network address translation (NAT) should give reasonable protection.

There are many websites that will perform a port scan and tell you what file-sharing and other services are visible through your router. For example "Shields Up" at

Shields-Up! report

Other such services exist, you can also do it yourself using a port scanner such as nmap

It is good practice to use user-ids and passwords to protect your file shares. Windows allows you to choose the level of security. Samba on Linux can work with at least some types of Windows file-sharing security (it's a while since I used it).

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To be honest, I only know nmap by name, I'd be a bit clueless of how to use it. It's nice that such services do exist (I'll use it shortly), and it's nice to know that being behind NAT is a good enough protection for the casual user. Do you think user IDs and passwords are a must, or the average Joe (like me) could do without that extra layer of security? I ask because it looks a bit boring to set up, and it would be unlikely that somebody breaks into my house and plugs a cable in my router just to access my files. – Camilo Martin Feb 10 '12 at 20:49
Tried the obvious: I can connect by name (\\bakemono\ ) and by LAN IP (\\\ ), but not by the router's IP, so I believe this means I'm in the safe. Also, security is really transparent to set up in Samba, unlike what it is in Windows. I never knew I could use passwords until I met smbpasswd. – Camilo Martin Mar 12 '12 at 5:44

A work around I use is to put a 3rd party firewall on XP (disable XP firewall), set a rule to only allow the ip address of your other PCs to be able to connect to the XP box, I use the old Sygate firewall for this on all my XP boxes. Sygate is no longer supported but works flawlessly for me.

Once installed you can allow or deny outbound using the popups when the show, and to set inbound for your network adapters go to Tools >Options> Network Neighborhood Tab in the sygate interface to configure inbound protection, Untick "Allow others to share my files and printers", do this for all network adapters you have using the drop down box to change adapters, then hit ok. Now go to Tools>Advanced Rules to allow the IPs and protocols/ports you need using the "add" button. I use Sygate free version 5.6.2808


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I see, so this will protect even the most unsafe of protocols if I restrict it to, say, That's nice to know! (And +1 for posting screenshots too) I've never used any third-party firewall on Windows. However, do you think I'd still need this, even if I'm constantly behind NAT? I've used the site RedGrittyBrick recommended, and it could not find open ports (It also makes me think, if I was designing a router, I'd make sure external connections could not reach file and printer sharing ports of the computers behind it... I'm just guessing). – Camilo Martin Feb 11 '12 at 5:14
Not sure if you need it but you may like it for some of its other features like outbound firewall. I use it because I have others on the same internal network I am using, so it blocks everyone else from my shares. – Moab Feb 11 '12 at 16:50

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