UPNP and recent Belkin routers OK
My Belkin FSD7230-4 wireless router has a firmware setting to disable UPNP connections. UPNP is OFF by default.
So that headline should probably read "*some* home routers are vulnerable..."
Cheers from Canada
Security mavens have uncovered a design flaw in most home routers that allows attackers to remotely control the devices by luring an attached computer to a booby-trapped website. The weakness could allow attackers to redirect victims to fraudulent destinations that masquerade as trusted sites belonging to banks, ecommerce …
on my SMC Barricade router, and now I can no longer control it. Typing 192.168.1.254 in my browser reports a 404. Niether can I telnet or ssh it.
In order to change anythong in the configuration I will have to use a paperclip to clear take it back to it's defaults. If I can remember my ISP user name and password.
UPnP is great. Rather than creating a port forwarding rule (which always leaves a certain port open), it only opens and forwards the port *while running the app which needs it*. Once the app closes, the port is also closed.
I'll rely on NoScript blocking Flash content that's not hosted on websites I explicitly trust, for now.
Gibson was slaughtered in the press for being a scare-mongering f*ckwit.
Whilst he - quite rightly - declared UPnP unsafe, he also declared just about every other interface & protocol available to a PC unsafe too.
Besides, turning UPnP off has been considered good practice since it was first introduced.
Think that until a couple of days ago it wasn't an issue as my aged BEFSR41 predated UPnP! However just got a WRT54GL and, as others have commented, during initial setup saw the enable/disable UPnP and without thinking disabled it! (Slight minus point was that it was enabled by default)
Also, interested to see that WRT54 also has the useful option of denying access to the settings web pages from the wireless interface which closes another potential (if unlikely in practice) harzard
I find it very tenious that the reason that this isn't a security flaw in flash is because flash is behaving the way it was designed too. This is complete rubbish.
It IS a security flaw in flash. I can see no justifiable circumstances why a flash script from the internet should be able to open a page to a private non-public ip address. It shouldn't be allowed.
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UPnP is supposed to be standardised, shame that in reality it isnt, every router has its own little foibles and bugs, many just plain dont work at all, or work once then crash. its been hell trying to write code to work smoothly with as many routers as possible. oh and someone said that the port forwarding vanishes when the application does, wrong, the program would have to explicitly send delete rule commands to the router.
Because the request is sent by the web browser, the upnp request _is_ from the internal network.
Do other viruses and trojans change your primary DNS? It seems like it'd be a rather useful thing to do, if you're so inclined.
...if you have an Xbox360 and use Live.
I'll guess we'll have to wait for that penguin powered games console and in the meantime keep ourselves amused with board games or something.
Alternatively I might have a look and see if I can create a firewall rule on my router to only allow non-PC's on my network to use UPNP...
The links on the article seem to imply that it uses the IP address of the router to give it access to UPnP.
So does this mean that if the router has a non default IP address (or is not the default gateway) then its actually going to be hard to get into? How long is it going to take to scan all the IP addresses in my 192.168.x.x address range?
"It IS a security flaw in flash. I can see no justifiable circumstances why a flash script from the internet should be able to open a page to a private non-public ip address. It shouldn't be allowed."
What a load of BS. I guess you haven't heard of an Intranet then? How would it be told it's on the internet or an intranet - some corp's have internal servers that -do- have external (firewalled) IP addresses that are accessed from inside the LAN so simply checking it's (local machines) IP wouldn't work.
I suspect you already know the answer to that and you're just angling for a "most predictable smart-alec post" award.
Of course the router is fit for purpose, it routes traffic from one place to another. I don't see any manufacturers advertising their products as totally secure, they just say "our router will route traffic".
Just because it doesn't say whether uPnP can be disabled on the box doesn't mean you have a legal right to buy it to find out, and then return it for a refund if it doesn't do what you want. Don't get rights mixed up with voluntary returns policies. If you specifically want functionality that isn't mentioned on the box, then you need to ask the reseller and if PC World tell you that uPnP can be disbaled but you then find it can't be, then you have a right to a refund. Of course, trying to get PC World to admit to telling you duff gen is another issue entirely....
I never switch on Upnp. Not only is it a bad practice, but in case you have 'smart' windos machines around, they will autodetect the 'feature' and use it to switch the ISP link on/off. So, say you have 4 machines connected and you close down one, all others loose their connection as well. This is what happened on an older speedtouch icm. windos XP.
It should be switched off by default - always - and I really see no reason for anyone using it at all. The same applies to stupid flash stuff as far as I'm concerned....
I see these regular stories on Reg about holes in routers etc. I've got a software firewall, noscript etc. etc. but I read the stuff above about NAT, port forwards, now UPnP, IPtables for routing and all that, and it's clear that my fragmentary knowledge of IP ("four numbers. Dots inbetween") doesn't cut it. I've two books on networking & they taught me nothing - they really were trivial. So, experts, please recommend a solid book or somewhere to start.
BTW I work in IT so I'm only a newbie in networks.
With google you can find many of these inforrmation resources. What you should start to learn are the fundamentals. Search for 'TCP/IP networking howto' and a lot will show up.
This is a reasonable page to get started:
I have learned my original TCP/IP knowlegde from a book connected to the Novell 3.12 NOS. It was a very comprehensive book and perfectly clear. It just does not cover all those 'new thingies' like NAT etc.
...came with UPnP enabled... but when (way back then) the service was enabled on my PC it used to use up half my CPU and bandwidth so I turned it off by disabling the service on my PC. Having done that, I figured I didn't need it on my router either and disabled it.
Can't see why people are arguing to be honest. It's cack - turn it off. Make sure when you buy a router that it CAN be turned off.
I wouldn't claim to be an expert, but I recall these two being good.
Data Communications, Computer Networks and Open Systems
# ISBN-10: 020142293X
# ISBN-13: 978-0201422931
Andrew S. Tanenbaum
# ISBN-10: 0130384887
# ISBN-13: 978-0130384881
There's a lot of overlap there, and I'm not sure they cover upnp which is relatively recent.
Since I know that only a very few ports are required for the stuff I use and they are all on one PC on my network I've never used UPnP. Mind you, as I have a linksys router I binned the standard firmware and moved to Tomato - much better than the standard stuff and has UPnP off by default.
Looking back 7 years ago today, just about every other interface & protocol was insecure. (pre XP... at a time when people were buying Windows ME on new computers! Most users had fat32 file systems!) I wish people had listened, since nobody really did, we have russian computer gangs, massive bot nets, turks defacing websites, chinese pen testing DOD computers, spam, prolific viruses and nigerian royalty.
...if you don't go to dodgy websites in the first place where these people are likely to have put the crafted flash, then you haven't got a problem.
Again - common sense and having half a brain prevails.
I'm leaving my UPnP on, thankyou very much, even if I don't have many applications that use it.
"The problem resides in Universal Plug and Play"
And nothing more really need be said. The brainless f*ckwits that can't set up their networks without UPnP are going to get infected regardless of Flash.
And those of us who can follow simple directions don't need UPnP, so we turn it off on every device before allowing an Internet connection.
OK, so someone will write (or more probably copy) a nice tutorial on how to use your router safely, or some other networking issue. You know, "Networking for Newbies" type of stuff would fit the bill. And place the exploit there. How about it? When you google for this, this site might show up. You might notice it's not what you were looking for only after you opened it. Happens all the time to me.
Don't think that only pr0n and h4x0r websites can be "dodgy"...
Whoever designed the XBox Live networking should be flayed. It does indeed like to use UPnP to control your router:
This idiocy from the clowns who want to bring you Trusted Computing
All those saying just switch it off an configure your router manually are missing the point. Most people who benefit from upnp don't have a clue how to do this.
Telling them to switch off upnp is effectively telling them to give up webcam chats with their loved ones via skype or msn, give up having a tech savvy friends help them with their pc via remote assistance, give up playing online games on their pc or games console - basically give up any application that requires ports to be opened in nat a firewall.
As with most things, upnp is safe as long as you can prevent a malicious application from running on a pc within the firewall. The fact that flash can act as a malicious program with regard to upnp is the problem. Flash should be modified to specifically prevent it from issuing upnp commands. It is far more practical to do this than to expect millions of non-technical users to modify their router settings.
I'm a bit confused by comments about this model. Mine is about 2yr old and running the original firmware (v4.30.7) and it does not have any UPnP that I can find. Supposedly it is listed under "Applications & Gaming" but I can't find anything. I was thinking this would be the time to change the firmware, but maby I'll just leave well enough alone.
Some routers are 'certified' as "Xbox Live Compatible", which is a marketing exercise to promote the router for typical home use. Don't fall for it - it just means the router has UPnP enabled as standard. You don't need UPnP on a typical home router and if you're about to buy one, ensure that it can be disabled from the admin screens, especially in light of this exploit.
To make XBL work on a router without UPnP running, do the following (should work for common Netgear or DLink interfaces, else you'll have to work out the equivalents for your router):
1. Tell the router to always give the Xbox (identified by its MAC address) the same IP each time -OR- set the Xbox to have a static IP. Either way the goal is to make sure the Xbox always has the same IP.
2. Create a new service called XBL88 and set it as TCP and UDP port 88. In the Netgears you can select TCP and UDP and have to specify the start and end port, just make them both 88.
3. Reapeat for a service called XBL3074 for port 3074.
4. In your firewall rules say that anything inbound for the XBL88 and XBL3074 services is forwarded to the IP address reserved earlier for your Xbox. This is two rules in 'Inbound Services' in the Netgears.
5. Make sure you apply changes as you go. Boot up the Xbox and confirm it has the correct IP in the Settings / Network blade. Test the connection to XBL, the NAT type should be 'Open'.
That's it. Forwarding the ports is what UPnP would have done dynamically for you.
with anybodies router what technical mindless bosh is this I don't even own a router and this seems highly suspect. Yeah ok I read it was unsafe and said duh along with everyone else at the time but heres my question what is flash doing that it needs to control your router.
Well I read teh GRC page years back, decided I had no need for UPnP and that it was kinda dangrous too boot. So on every Windows PC i have set up or rebuilt, and they do need rebuild regularly, I run unUPuP, and a couple of other GRC products. For example insuring that the message thingy is disabled. I am sure I can do these without the GRC products but it makes it easy.
I have UPnP turned off (if i remember) in my router, think it was the default, I never have any issues logging in at all, either via its DNS name or its IP address, turning port forwarding rules on so that I could use azureus was easy, azureus actual points you in teh direction of teh help (great app btw). So i have open ports, lovely, oh sorry no i dont cos I only turn those rules on when I want to torrent.
If a user dosnt wnat to be infected they should go out and learn how to secure their machines. They should learn to be more careful about what they click on, its not hard, just takes a little common sense, for companies to provide routers and other kit in a secure way as default, I am looking at Sky here, amoungest others, and for people actual selling teh kit to have a clue and be approachable and answer questions, its not hard people!!
Avoiding dodgy websites isn't so easy...
Never clicked a link in a search engine without checking the url?
Never followed a link that claims to tell you about a upnp exploit?
Never followed a link out of a spam email? (Go on be honest)
Never read hacking sites?
Never followed a link out of a wiki?
Perhaps Flash should be subject to the same kind of security restrictions that a java applet would be under, one of which is that it can only connect to the site it came from.
Just checked and my Netgear doesn't have a feature to turn uPNP off, only one to turn it *on* because, as the help text on the uPNP page says, "The default setting for UPnP is disabled. If disabled, the router will not allow any device to automatically control the resources, such as port forwarding (mapping), of the router." - which seems pretty clear!
@Death_Ninja/Chris/etc - I've got uPNP disabled (see above) and I don't have any problems my XBox360 on XBox Live - certainly it works enough to download content, get patches and get shot to bits in the Halo3 multiplayer beta. Is there something else I should be getting? Other than not shot repeatedly in Deathmatch of course.... :'(
Maybe I've just been lucky with my config - which'd be a novelty....
It's been a while since I had any reason to play with UPnP, but I vaguely recall that I needed to give myself admin rights before Windows would let me blow holes in my router. Is that still true?
If you need admin rights then this is a scare story. Any "security hole" that needs admin rights on the local machine to exploit is just FUD. (In this context, Raymond Chen is fond of the Douglas Adams line "It rather involved being on the other side of this airtight hatchway".) On the other hand, if you don't need admin rights to open ports on your firewall/router/whatever, then there's something wrong with your kit.
Of course, far too many people *are* using admin accounts and using IE to download and automatically run whatever the bad guys want, but UPnP is not part of that picture.
@ Steve: Thanks for clearing that up. It's fixed now, but it was on by default as David Shepherd had mentioned above. I find it a bit disheartening that Linksys would do that. Maby thats a good reason for switching to Tomato like Steve Pettifer did. (same Steve?)
I find these kinds of menus confusing. My eyes aren't what they used to be and it's easy to fool me with amateurish layout and odd vocabulary such as putting UPnP with passwords instead of with port forwarding. You'd think a company like Linksys would take a more professional approach.
To Robert Cross - XBL still works without the relevant ports forwarding through to the Xbox, but there are various restrictions in terms of what you can do. Simplest way is to go to your network blade in the Xbox and test your connection to XBL. Make a note of the type of NAT reported then go here to see the implications.
UPnP or manual forwarding will make it of type "open" which is the most compatible.
my Bt white-slab-of-plastic-router-thingy went down and while trying to suss it I came across this:
The BT Home Hub contains code that is covered by the GNU General Public License (GPL). In accordance with the GPL, BT makes the relevant code available for download below.
code is on <http://www.btyahoo.com/broadband/adhoc_pages/gplcode.html>
FYI if you want to poke around.
BTW thanks for the book recommendations above, much appreciated.
From what I can see the problem isn't with UPnP but with the home gateway router manufacturers' implementation of it.
Take a look at "Understanding UPnP™: A White Paper" at http://www.upnp.org/resources/whitepapers.asp. Once you get past the Windows ME logo and the 'future tech' verbiage it comes down to an appliance advertising the services it offers.
Now look at consumer internet gateway routers (IGR) and ask why a consumer IGR needs to allow its internet connection settings or password to be changed via UPnP.
I can see why an IGR would allow UPnP to configure port forwarding (external to internal) - this replaces the process that I would otherwise need to undertake manually – but why an IGR should offer any other service is beyond me.
If the only UPnP request that my IGR recognises is one that opens an external port then I’m happy – that’s what I thought it did and my internal application firewall (ZoneAlarm) will let me decide whether a specific application is allowed to listen for incoming internet requests.
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