are belong to us.

It can't be that bad, can it?

Tweed with the patches on the elbows, thanks.

At least one of Telstra's name servers are vulnerable.

203.215.3.43

I wonder if Virgin Media would mind me injecting my own subdomain onto their DNS to replace the boring ubr.locale.blueyonder.co.uk format? :)

According to the site, AT&T Wireless is susceptible when using the isp.cingular APN. Not sure about the wap.cingular APN, but I would venture to guess the condition is the same. DNS server assigned is 209.183.35.2.

Paris, possibly susceptible, but the firewall or nat router may be interfering with her port selection policy.

Shaw Cable in Canada seems OK:

Your name server, at 64.59.184.15, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.Requests seen for b14aed6a1cd3.toorrr.com:

64.59.184.15:21877 TXID=14695

64.59.184.15:23901 TXID=9436

64.59.184.15:30578 TXID=50420

64.59.184.15:20735 TXID=39373

64.59.184.15:9712 TXID=46561

Over here in SK, my ISP is wide open.

59.0.159.86

Korean Telecom/KORNET

I am on holydays in France and connected to Orange and it seems safe ...

Your name server, at 218.102.23.228, appears vulnerable to DNS Cache Poisoning.

I sent this by email to PCCW execs weeks ago, but no response, and no change.

DNS needs to be "patched" here too

but I can bet NTT is on to it...

I know Tiscali has been something of a target for bad press before but their servers are all good according to the Check My DNS widget.

The fact that some organisations take a month to roll out an urgent security patch isn't an excuse. It's just another problem that those organisations needs to sort out.

Taking time to test thoroughly is good, but there needs to be a sliding scale of risk due to not testing and risk due to not patching.

Your name server, at 203.121.65.39, appears vulnerable to DNS Cache Poisoning.

I checked my Virginmedia DNS last night and it reported okay.

I tested the one at work this morning and its not patched (but I'm not surprised at that result).

Okay... mine's the one with the CV's in the pockets....

195.27.150.140 used by 3 is vulnerable... and if you are using their wireless broadband modem you cant hardcode DNS server addresses

You list OPAL as bein unpatched but AOL & TalkTalk were patched a while back and pass the "Check Your DNS" test.

small ISP... got WiMax air interface... works tops... but urgh! not when their DNS's are vulnerable... 213.172.33.34 and 213.172.33.35... sent their admins an email this morning...

Qu: large ISP or small ISP more responsive to something like this?

Silo - Good luck to you mate, knowing KORNET, the DNS might be patched some time in the next 10 years (along with the rest of the korean infrastructure).

A big well done to Zen for getting theirs done so quickly. I ran the test the first time it was announced and it came up with the "safe" notice.

Another reason to be happy wtih moving from BT in my own personal "phorm" protest :)

Top marks to my ISP, Eclipse. The test shows they pass :)

Stop reading the reg and get back to your holidays, Geek!

Your name server, at 87.194.0.66, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.

Requests seen for 0fdf9cf5fbac.toorrr.com:

87.194.0.66:23676 TXID=55910

87.194.0.66:45831 TXID=52634

87.194.0.66:22724 TXID=59957

87.194.0.66:35609 TXID=51197

87.194.0.66:5856 TXID=45189

Your name server, at 213.130.128.31, appears vulnerable to DNS Cache Poisoning.

g0-1-41.ac3-u1-sal-uk.as15444.net -> netdnscache01.eng.net

It's high time users should learn to verify SSL certificates of sites of any importance to them. This also nullifies most dangerous effects of DNS poisoning - which is not a new attack type, BTW.

IIRC they snat you away to their own servers anyway, we need dns over ssl...

Err - wot the title says

Did wonders for me, updated the linux servers bind daemon and it killed everything i really enjoyed manually rebuilding what the patch had done...

JOY.

6 months to bring out this patch jeez...... fair played to the guy who found it though and kept it hush hush instead of taking advantage of the problem.

Firstly, Virgin started patching for this bug a *month* before the public announcement. We're really friendly with our DNS supplier :-)

Secondly, OpenDNS works fine on Virgin Media, we don't "snat you away" (whatever that means) in any way. I suggest you update your memory with a fact or two :-)

I can confirm that VM and Pipex seem ok.

Have Bethere patched this yet?

UK Online's DNS servers are vulnerable. They're owned by Sky but I don't know if they use the same servers as Skybroadband.

Griffin Internet's recursive DNS servers are patched. Testing passes.

Be are in the clear (unsurprising, since they are the same as O2).

Karoo's 'opt-out' DNS servers check out OK. Not sure about the default one's though.

As any Be customer knows, their DNS is crap and you should be using OpenDNS anway :o)

No worries on home broadband (Smart Telecom), but when I ran the check using Vodafone Ireland's mobile internet, I got the following response:

"Your name server, at 213.233.128.19, appears vulnerable to DNS Cache Poisoning.

All requests came from the following source port: 27597"

So unless Voda is doing something that this tool has not been setup to handle, there might be an issue.

UKOnline/Easynet seem to have patched their DNS servers within the past few hours.. so all is okay here now!

In case you have not seen it, here is AT&T's official statement on this vulnerability:

"AT&T Response: US-CERT DNS Security Alert- announced July 8, 2008

On July 8, 2008, US-CERT issued a Technical Cyber Security Alert TA08-190B with the title 'Multiple DNS implementations vulnerable to cache poisoning.' This alert describes how deficiencies in the DNS protocol and common DNS implementations facilitate DNS Cache poisoning attacks. This vulnerability only affects caching DNS servers, not authoritative DNS servers. This alert instructed administrators to contact their vendors for patches.

The DNS community has been aware of this vulnerability for some time. CERT technical bulletin http://www.kb.cert.org/vuls/id/252735 issued in July, 2007, identified this vulnerability but at the time no patches were available from vendors.

AT&T does not disclose the name of its DNS vendors as a security measure but has implemented a preliminary patch that was available in January, 2008. The latest patch for alert TA08-190B is currently being tested and will be deployed in the network as soon as its quality has been assured.

AT&T employs best practices in the management of its DNS infrastructure. For example, the majority of AT&T's caching DNS infrastructures have load balancers. Load balancers decrease the risk significantly because hackers are unable to target specific DNS servers. As with all patches to software affecting AT&T's production networks and infrastructure, AT&T first tests the patches in the lab to ensure they work as expected and then certifies them before deploying them into our production infrastructure.

Conclusion:

Security is of paramount importance to AT&T. AT&T has a comprehensive approach to the security of its networks and supporting infrastructures. AT&T is meeting or exceeding our world-class DNS network performance measures. We will continue to monitor the situation and will deploy software upgrades, as warranted, following our structured testing and certification process."

End of quote.

Note that:

1) They claim this is the same problem reported a year ago and for which they have already patched.

2) They claim load balancers will protect against this bug. All evidence to the contrary, they have not changed their statement.

3) They claim they do not disclose the vendor of their DNS, but also claim this is a bug in BIND which they have also patched.

4) They do not acknowledge that this is an issue with the DNS protocol, rather they act as if it is a bug in a software application.

Verizon patched everything on July 10th. What is taking AT&T so long?

I'm on comcast, and I just failed the test. A little disconcerting considering they state at their test site "Note: Comcast users should not worry.". What amazes me is that these companies dont get it and carry on just as they did before....

We have BT here (albeit a business line), and 194.72.0.98 comes up clean (haven't tried our secondary which is 194.72.9.38).

Your name server, at 68.238.96.36, may be safe, but the NAT/Firewall in front of it appears to be interfering with its port selection policy. The difference between largest port and smallest port was only 36.

Please talk to your firewall or gateway vendor -- all are working on patches, mitigations, and workarounds.

--------------------------------------------------------------------------------

Requests seen for 87bba0bc964e.toorrr.com:

68.238.96.36:39655 TXID=27775

68.238.96.36:39670 TXID=11599

68.238.96.36:39646 TXID=23973

68.238.96.36:39682 TXID=39241

68.238.96.36:39652 TXID=32366

Other repeat runs of the test give a port range no larger than 70, and as few as 23. Doesn't this make it easier for the bad guy to win the race, or is it the router I am sitting behind that is doing this?

Running the test on my Verizon connection got me the "appears to be safe" message, along with the "make sure the ports ..." bit.

I didn't get the port range message you got, so it might well be your router settings.

Your name server, at 151.164.14.196, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.

--------------------------------------------------------------------------------

Requests seen for 4f5029e03184.toorrr.com:

151.164.14.196:18902 TXID=4222

151.164.14.196:44489 TXID=45620

151.164.14.196:2701 TXID=65443

151.164.14.196:57187 TXID=34670

151.164.14.196:1526 TXID=56490

Note: dnsnode1-x4.stlsmo.sbcglobal.net [151.164.14.196]

Appears to be sorted

Your name server, at 195.74.113.58, appears to be safe,

Requests seen for f3050306b5b3.toorrr.com:

195.74.113.58:13414 TXID=52945

195.74.113.58:49222 TXID=48220

195.74.113.58:45941 TXID=16935

195.74.113.58:26171 TXID=13951

195.74.113.58:50179 TXID=10996

Your list may not be that accurate AOL runs on the Carphone Warehouse servers and appears not to be suseptible to this attack.

Boffin for obvious reasons

"Demon Internet was reported as potentially being vulnerable"

No. It produces similar messages to that produced by Verizon e.g

'Your name server, at 194.159.187.34, may be safe, but the NAT/Firewall in front of it appears to be interfering with its port selection policy. The difference between largest port and smallest port was only 247.

Please talk to your firewall or gateway vendor -- all are working on patches, mitigations, and workarounds.'

Your name server, at 195.93.61.23, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.

--------------------------------------------------------------------------------

Requests seen for 9184eaf37373.toorrr.com:

195.93.61.23:29828 TXID=42138

195.93.61.23:20642 TXID=48288

195.93.61.23:36031 TXID=14818

195.93.61.23:51089 TXID=49774

195.93.61.23:46036 TXID=9067

As I said in earlier post this is Carphone whorehouse server

Per dns-oarc.net,

209.183.35.23 (alpinetdns.mycingular.net) appears to have GREAT source port randomness and GREAT transaction ID randomness.

But it still fail's Kaminsky's (Doxpara) test.

Paris, a great source of port randomness.

Somewhat to my surprise. Somebody at Telus is paying attention.

The thing I find interesting is that some very large ISPs seem to have no mechanism in place for fast tracking critical changes. Sometimes a patch is so important and so urgent that if it makes the system fall over, that's still a better situation than running without the patch.

Your name server, at 64.128.189.114, appears vulnerable to DNS Cache Poisoning.

Looks like they have fixed theirs as well:

Your name server, at 66.90.132.162, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.

--------------------------------------------------------------------------------

Requests seen for 73f58c44c681.toorrr.com:

66.90.132.162:7606 TXID=61558

66.90.132.162:23192 TXID=64573

66.90.132.162:1926 TXID=37783

66.90.132.162:58791 TXID=26127

66.90.132.162:36230 TXID=12505

Configuring my router to use the DNS cache at 194.168.8.100:

Your name server, at 194.168.8.109, may be safe, but the NAT/Firewall in front of it appears to be interfering with its port selection policy. The difference between largest port and smallest port was only 225.

Please talk to your firewall or gateway vendor -- all are working on patches, mitigations, and workarounds.

Requests seen for 27e658dcb4c1.toorrr.com:

194.168.8.109:32901 TXID=41131

194.168.8.109:32851 TXID=63188

194.168.8.109:32796 TXID=9462

194.168.8.109:33009 TXID=10296

194.168.8.109:32784 TXID=60013

And again (this time with 194.168.4.100 configured as secondary):

Your name server, at 80.7.128.36, may be safe, but the NAT/Firewall in front of it appears to be interfering with its port selection policy. The difference between largest port and smallest port was only 194.

Please talk to your firewall or gateway vendor -- all are working on patches, mitigations, and workarounds.

Requests seen for 1817ba74d9ed.toorrr.com:

80.7.128.36:15532 TXID=36617

80.7.128.36:15726 TXID=49120

80.7.128.36:15605 TXID=34601

80.7.128.36:15700 TXID=14672

80.7.128.36:15604 TXID=50260

Switching to OpenDNS (208.67.222.222):

Your name server, at 208.69.34.8, appears to be safe, but make sure the ports listed below aren't following an obvious pattern.Requests seen for de290b751743.toorrr.com:

208.69.34.8:31815 TXID=37200

208.69.34.8:4651 TXID=52861

208.69.34.8:54638 TXID=29577

208.69.34.8:41802 TXID=59604

208.69.34.8:19492 TXID=1674

For reference,

194.168.8.109 is winn-dnsbep-1.server.virginmedia.net

80.7.128.36 is oxfd-dnsany-1.server.virginmedia.net

To VirginMedia: it's no good the DNS cache randomising request ports if it's behind a NAT which just maps the ports back to something more predictable. As I understand the vulnerability, unpredictability of port numbers needs to be maintained across each network boundary, or else an attacker on the predictable side (outside the NAT in this case, if it is indeed a NAT that's the problem here and not the DNS cache) can still spoof responses.

It's also not much good randomising ports if you're still in a 200-ish range (adding only 8 bits of uncertainty to the 16 in the TXID, when the recommendation is to go to almost 32 bits).

Finally, there's no need to be so proud of starting work on it a month before Kaminsky published. Daniel Bernstein has been saying since at latest 2001 that DNS request ports should be randomised: http://cr.yp.to/djbdns/forgery-cost.txt

The article incorrectly states that Bell Canada is vulnerable. I used the test when I first heard about the problem and it said everything was fine. Just re-checked with the same result. As much as I despise Bell, they must have done the right thing. Either that, or the tool to check for the exploit is not working properly.

Thanks. Does this mean that subscribers who are getting the "port range too narrow" or "ports may follow a predictable pattern" test error are using name servers that are not patched properly?

Or is the test error an artifact of how NAT treats DNS lookup requests between the unwashed masses and the hopfully heavily armored DNS and LAN/WAN infrastructure of our trusty ISP of choice who shares much public space with many many NATed addresses?

If the narrow range, or patterned port assignments test errors behind every NAT wielding ISP are still a vulnerabilty, then I must be missing something.

I blame supernetting for the error, bring on IPV6 already!

<orderlies quickly descend to escort the anonymous coward into a wrap-around jacket and away from the computer in the recreation room, there is great struggle>

Anonymous Coward said:

"Does this mean that subscribers who are getting the "port range too narrow" or "ports may follow a predictable pattern" test error are using name servers that are not patched properly?"

Well, my latest tests of Demon produce:

"Your ISP's name server, 194.159.187.38, appears to be using the name server written by Nominum, which has effective protection against the newly discovered attacks despite the limited port range. Nominum is working to expand the port range for even greater protection, but there is no reason for concern at this time."

but also

"Your name server, at 194.159.187.34, may be safe, but the NAT/Firewall in front of it appears to be interfering with its port selection policy. The difference between largest port and smallest port was only 171."

(which is the same as previously reported for this server)

So now I'm confused. Are Demon using different versions of Nominum on different servers? Or is their patching not complete? Perhaps someone who is more savvy than me could explain what's going on here.

"Demon Internet was reported as potentially being vulnerable, because a Firewall or NAT in front of the DNS server "appears to be interfering with its port selection policy," according to Kaminsky's test."

I would guess Demon's firewalls INTENTIONALLY interfere with the port selection. Our Checkpoint firewalls alter both the port and the Id number used, specifically to mitigate the issue under discussion (and the server guys have applied the necessary patch) but the Check My DNS site still thinks we are vulnerable.

Your name server, at 80.58.61.250, appears vulnerable to DNS Cache Poisoning.

Telefonica couldn't care less about its subscribers. Fortunately the show equal care as to what their subscribers do.

Your name server, at 195.186.1.110, appears vulnerable to DNS Cache Poisoning.

All requests came from the following source port: 47043

Swisscom (Switzerland) primary DNS server for ADSL customers

My understanding is that if you randomise the port but only within a range of (say) 256 ports, then you have 24 bits of randomness including TXID. So even if the attacker can only get one packet in before the valid response, then they have a better than 1 in 17 million chance of success. According to Kaminsky's blog, the attacker can make a couple of thousand attacks (on different subdomains) per second - presumably this depends mostly on connection speeds. 8 thousand seconds is over 2 hours.

Now, 2 hours is a moderately long time to flood a server without anyone noticing. It's a very long time if there's something looking for such attacks in real time, although what a server can usefully do if it detects a series of attacks I'm not sure.

However, if my rough calculation is orders of magnitude out in the bad direction (for instance, suppose the attacker can reliably get 100 spoof responses in before the genuine response) then I don't see how the protection is adequate. It might take under a minute of activity to poison a DNS cache. That activity might conceivably be distributed across time and/or a botnet to reduce the chances of detection. If a large botnet were to devote its time to attacking such "24 bit" DNS servers, then it would successfully poison some of them, wouldn't it?

Perhaps Kaminsky can explain why a range of a couple of hundred ports is good enough. I haven't analysed the issue at all, I'm just repeating what I've read from Kaminsky and others. But my suspicion is that the warning is there for a reason, and the reason is that a narrow port range is not a full fix.

On the NAT issue: it doesn't matter whether the port randomisation is done by the DNS resolver or by the NAT, except that:

1) If the resolver is less random than the NAT, then you're somewhat more vulnerable to an attacker inside the NAT than outside (this is what happens if the NAT is fixed and the resolver isn't).

2) If the NAT constricts the port range of the resolver, then you're somewhat more vulnerable to an attacker outside the NAT than one inside.

Combining the two cases, if there are attackers both inside and outside the NAT then you're as protected as the worst case of port predictability. So what we want is for all resolvers and all NATs to randomise ports across as wide a range as possible.

Presumably if there's a "bad" NAT between you and a "good" DNS server, then Kaminsky's test would report you clean (because it only sees the requests from the fixed caching resolver), but actually you'd be vulnerable even if the non-caching resolver in your OS is patched, because the randomised port choice is rendered predictable by the NAT. So depending on network topology, there may be cases where your own domestic firewall/router makes you vulnerable to an attacker inside your ISP's subnet, even though everything else is fixed. Do ISPs route packets directly from one customer IP to another? What brands of firewall/router randomise ports adequately?

I'm sure Kaminsky will have all the answers at Black Hat. Or someone else will provide them sooner.

This is suprising...

Your name server, at 68.28.242.91, appears vulnerable to DNS Cache Poisoning.

All requests came from the following source port: 45521

Due to events outside our control, details of the vulnerability have been leaked. Please consider using a safe DNS server, such as OpenDNS. Note: Comcast users should not worry.

--------------------------------------------------------------------------------

Requests seen for d143efecae0d.doxdns5.com:

68.28.242.91:45521 TXID=5971

68.28.242.91:45521 TXID=14822

68.28.242.91:45521 TXID=5783

68.28.242.91:45521 TXID=39914

68.28.242.91:45521 TXID=34212

It is a wireless broadband link, would that be why they do not randomize the port?

I am ashamed of you ElReg - only a white Paris? Please make an icon out of this so we can truly express our opinions:

w w w.rude.com/steverudeman - take out the spaces

Just exactly how is disclosing this vulnerability to the wild making the internet safer? Maybe the name Blackhat has the insinuated connotation for these security researchers.

We (where I work) have the joy of outsourcing our network management to ****. This seems insanity to me, but it's obviously a choice for upper management, not us techies.

Anyway - the responsef from **** was that we are not vulnerable because the servers only serve answers for trusted clients.

Which totally misses the point - if you allow your clients access to the internet, then they're vulnerable.

So - if your company has external people managing your DNS (or other core services) - don't forget to JUMP ON THEM.

Anonymous & blanked company name for (hopefully) obvious reasons.

I shouldn't really expect anything less to be honest.

Average 8% packet loss and 35 UK notes a month here in sunny Montevideo for a 1.5 smeg connection ;-)

Your name server, at 200.40.220.226, appears vulnerable to DNS Cache Poisoning.

All requests came from the following source port: 33208

Requests seen for 7a29f8f05811.doxdns5.com:

200.40.220.226:33208 TXID=23352

200.40.220.226:33208 TXID=39952

200.40.220.226:33208 TXID=41029

200.40.220.226:33208 TXID=3363

200.40.220.226:33208 TXID=57739

Thumbs down as Paris is always getting thumbs up.

Only certain regions. Also at risk in Canada are Navigata and Westel:

204.244.3.129

204.244.3.130

Testing my recursive DJB servers produces "great!" results, semingly (from mailing list comments) it was DJB who suggested randomising the source ports as a security measure in the first place.

(Tux as DJB is a *nix only app)