Taking about a Microsoft VPN maybe? Don't they have an HTTPS tunnel for this?
Josh Luthman Office: 937-552-2340 Direct: 937-552-2343 1100 Wayne St Suite 1337 Troy, OH 45373 On Sep 20, 2016 1:08 PM, "Paul Stewart" <[email protected]> wrote: I’ve seen some custom VPN applications run over 445 and shook my head as to why…. We limit our filtering specifically to SMTP, DNS, and UPNP type stuff where attacks/misuse are most common … On Sep 20, 2016, at 11:20 AM, Ken Hohhof <[email protected]> wrote: I agree with what Lewis said. Ports 135-139 and 445 are well known ports assigned to Windows networking and have no business being on the open Internet. There should be a strong presumption that outbound traffic on these ports is malicious traffic from a worm like Blaster trying to propagate over the Internet. Best case, a customer has misconfigured something to send LAN traffic over a WAN connection. There are many pros and zero cons to blocking this traffic. Do not get hung up on the word “blocked”. This is not a Net Neutrality issue. NetBIOS/SMB is LAN traffic not WAN traffic, if someone needs it to go site-to-site, then it should be inside something like a VPN. *From:* Stefan Englhardt <[email protected]> *Sent:* Tuesday, September 20, 2016 9:26 AM *To:* [email protected] *Subject:* Re: [AFMUG] everyone should be blocking SMB ports We say our customers: You get free unblocked access. So we dont block. If we see a problem we block and notify the customer. *Von:* Af [mailto:[email protected] <[email protected]>] *Im Auftrag von *Dave *Gesendet:* Dienstag, 20. September 2016 16:21 *An:* [email protected] *Betreff:* Re: [AFMUG] everyone should be blocking SMB ports +1 On 09/20/2016 09:12 AM, Jon Bruce wrote: +1 On 9/20/2016 10:01 AM, Lewis Bergman wrote: I am a firm believer in the stance that as your ISP, I am not your mommy. We did no filtering or firewalling for our customers. The only exception being the blocking of certain traffic that had no business being on the open Internet. This is one of those things. On Tue, Sep 20, 2016, 7:21 AM Richard Strittmatter <[email protected]> wrote: We block, have for years and years.. Richard Strittmatter *From:* Af [mailto:[email protected]] *On Behalf Of *Mike Hammett *Sent:* Monday, September 19, 2016 11:59 AM *To:* [email protected] *Subject:* Re: [AFMUG] everyone should be blocking SMB ports Yes, block. ----- Mike Hammett Intelligent Computing Solutions <http://www.ics-il.com/> <https://www.facebook.com/ICSIL> <https://plus.google.com/+IntelligentComputingSolutionsDeKalb> <https://www.linkedin.com/company/intelligent-computing-solutions> <https://twitter.com/ICSIL> Midwest Internet Exchange <http://www.midwest-ix.com/> <https://www.facebook.com/mdwestix> <https://www.linkedin.com/company/midwest-internet-exchange> <https://twitter.com/mdwestix> The Brothers WISP <http://www.thebrotherswisp.com/> <https://www.facebook.com/thebrotherswisp> <https://www.youtube.com/channel/UCXSdfxQv7SpoRQYNyLwntZg> ------------------------------ *From: *"That One Guy /sarcasm" <[email protected]> *To: *[email protected] *Sent: *Monday, September 19, 2016 11:57:44 AM *Subject: *Re: [AFMUG] everyone should be blocking SMB ports Whats the WISP consensus on blocking those ports at the edge? also, whats the best religion? if Ford or Chevy better? Whats the greatest sports team? On Mon, Sep 19, 2016 at 11:50 AM, Zach Underwood <[email protected]> wrote: My work has its own IP address and get upstream from atnt and charter. The smb ports are not blocked. Zach Underwood (RHCE,RHCSA,RHCT,UACA) http://ZachUnderwood.me <http://zachunderwood.me/> advance-networking.com On Sep 19, 2016 12:47 PM, "Josh Luthman" <[email protected]> wrote: Cable/Telco probably. WISP? I dunno... Josh Luthman Office: 937-552-2340 Direct: 937-552-2343 1100 Wayne St Suite 1337 Troy, OH 45373 On Mon, Sep 19, 2016 at 12:47 PM, Sean Heskett <[email protected]> wrote: i think everyone has been blocking those ports since 1998-ish (or at least you should be) -sean On Mon, Sep 19, 2016 at 10:22 AM, Zach Underwood <[email protected]> wrote: This was written from the view point of windows AD setup can affect home users too since MS makes people use MS live accounts to log in to windows. *Problem:* Outside servers can get username/domain/password hash. Once a remote server has the login info they could connect to VPN, Office365 or an other service that using AD domain user info. See attachment for example. I got the example from a VM with a test account on it. *Details:* Microsoft based browsers like IE and Edge can be induced to make a outbound smb connection to a remote server. In this connection Microsoft will send over username, domain, and password hash. The remote server then can do a decryption of the password hash using brute force, password, dictionary and rainbow tables. *Fix:* The fastest way to stop this is to block all of the smb networks ports on the edge firewall for incoming and outgoing. The ports are 137-138udp, 137tcp,139tcp, 445tcp *Sources:* http://www.zdnet.com/article/windows-attack-can-steal-your- username-password-and-other-logins/ *Testing site*: https://msleak.perfect-privacy.com/ -- Zach Underwood (RHCE,RHCSA,RHCT,UACA) My website <http://zachunderwood.me/> advance-networking.com -- If you only see yourself as part of the team but you don't see your team as part of yourself you have already failed as part of the team. -- <image001.jpg>
