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Microsoft Live Account Credentials Leaking From Windows 8 And Above (hackaday.com)
An anonymous reader writes: Discovered in 1997 by Aaron Spangler and never fixed, the WinNT/Win95 Automatic Authentication Vulnerability (IE Bug #4) is certainly an excellent vintage. In Windows 8 and 10, the same bug has now been found to potentially leak the user's Microsoft Live account login and (hashed) password information, which is also used to access OneDrive, Outlook, Office, Mobile, Bing, Xbox Live, MSN and Skype (if used with a Microsoft account). The bug itself seems to be present in all Windows systems since Windows 95 / NT, although only Windows 8 and above are effectively compromised. To see if your machine is affected, you may want to check the public demonstration of the exploit, set up by the guys from [Perfect Privacy] and based on [VladikSS] original work. Basically, the default User Authentification Settings of Edge/Spartan (also Internet Explorer, Outlook) lets the browser connect to local network shares, but erroneously fail to block connections to remote shares. To exploit this, an attacker would simply set up a network share. An embedded image link that points to that network share is then sent to the victim, for example as part of an email or website. As soon as the prepped content is viewed inside a Microsoft product such as Edge/Spartan, Internet Explorer or Outlook, that software will try to connect to that share in order to download the image. Doing so, it will silently send the user's Windows login username in plaintext along with the NTLMv2 hash of the login password to the attacker's network share.
I always found it odd when accessing network shares between users with the same name and password that it never prompted me for one.
Yes, the use of the word "share" can be misconstrued in this context.
I would assume, perhaps wrongly, that in this instance "share" means anywhere that Outlook, IE, Edge, etc can reach...
Meaning anywhere on the internet, otherwise this vulnerability wouldn't be as big of a deal.
We play the game with the bravery of being out of range
Yes, the use of the word "share" can be misconstrued in this context.
Think of it in the context of heroin users "sharing" a needle, or when a child coughs directly into your face to "share" his cold with you.
Just cruising through this digital world at 33 1/3 rpm...
If I block outbound CIFS/SMB connections at the firewall, this should solve the issue, correct?
My eyes reflect the stars and a smile lights up my face.
trying to navigate all of Microsoft's many convoluted username/password schemes.
For the love of all that is holy.. consolidate some of these logins, Microsoft!
If we had an article for every security vulnerability/backdoor found in a Microsoft product, it'd be impossible to find anything else on Slashdot.
What's newsworthy in this case is that the vulnerability remains unpatched since 1997. That is older than some of my kids. That's almost old enough to drink.
I am not your blowing wind, I am the lightning.
If we had an article for every security vulnerability/backdoor found in a Microsoft product, it'd be impossible to find anything else on Slashdot.
What's newsworthy in this case is that the vulnerability remains unpatched since 1997. That is older than some of my kids. That's almost old enough to drink.
That's not unprecedented either: http://www.bbc.com/news/techno...
And plenty old enough to drink in Europe ;)
It can be over the internet.
Confusion between the local network and the internet is the source of the problem. Windows is supposed to automatically log in to LOCAL shares. Instead it will automatically log in to shares anywhere on the internet, when it sees a link to a share.
The critical thing that isn't getting enough attention here is that it requires IE to work. If you visit the test site in Chrome or Firefox it tells you to come back in IE. So it's not nearly as bad as it first appears.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
(Per the results I saw with the testing tool.) That means they could get e.g. VPN or email credentials, too.
I'd prefer if it didn't do much distinction. One compromised device inside a local network shouldn't be enough to escalate it to control every device inside. If you trust devices on a basis "its in our network", then you are doing something wrong.
and the defaults are horrible.
To protect yourself, goto Internet Options -> Security Tab
"Custom level...." -> scroll to bottom, change "User Authentication - Logon" setting from "Automatic login only in Intranet zone" to "Prompt for user name and password".
Repeat for all four zones. Your Internet Explorer install will no longer leak password hashes.
Then do yourself a favor and use another browser for daily browsing.
That's almost old enough to drink.
And now you've made me feel old.
Time to offend someone
I'm not sure what's more pathetic here, the age of this Microsoft bug, or the fact that so many firewalls do NOT block the relevant outbound TCP ports by default.
Seems both are equally as culpable.
Most companies let people reach out to wherever they want.
The vast majority of filtering/firewalling is done for the opposite direction - blocking shit coming in that doesn't already have an established connection.
I can see how this is one of those "it's not a bug, it's a feature" arguments.
Probably "unpatched" because some big customer of MS is using this "feature".
Though, why they wouldn't just determine the internal vs. external links by using site-and-services and/or IE zone profiles... I don't know.
My eyes reflect the stars and a smile lights up my face.
You just answered the question. Probably the same big company using the bug is probably the same one that has many internal sites marked as external sites for whatever reason.
here's an amusing video showing how simple it is to crack password hashes. teh NTLMv2 hash is only about 4 times slower than the hash he uses in the video.
Looks like they missed this in regression testing then
Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.
Or you know.. go to any Starbucks, label your machine "free movies" or make a battery powered hotspot with a captive portal page that sends them to the cifs share and start collecting hashes.