Another DNS Flaw Found, Patched

darthcamaro writes "Remember the big DNS flaw that Dan Kaminsky 'discovered' last year? Well, it looks like another flaw in DNS has just been patched. This time it's an item that affects DNSSEC, which was supposed to be the savior for the Kaminsky flaw. The good news, though, is that this time, the issue is relatively minor and DNS has already been patched. 'The flaw is specific to certain usages of DNSSEC,' Joao Damas, senior programming manager of the ISC told InternetNews. 'It is strongly advised that all BIND DNSSEC deployments update in case they are using the particular pattern affected (DSA keys in some cases) and to prevent coming across the problem in the future unexpectedly.'"

Comments

any relation to the Ubuntu update?

[LingNoi]

Is this somehow related to the bind DNS updates for ubuntu desktop that got pushed yesterday?

Re:any relation to the Ubuntu update?

[WarJolt]

Your home ubuntu machine or windows machine won't be effected directly by this.

Re:any relation to the Ubuntu update?

[Sir_Lewk]

Even if we are running a DNS server on one of them?

Re:any relation to the Ubuntu update?

[Aladrin]

I'm happy not knowing exactly how my car runs and most users are happy not knowing exactly how their operating system runs.

Unless you know everything about absolutely everything in your life, you have no room to talk about people not knowing how their computers work.

Re:any relation to the Ubuntu update?

[peektwice]

You are aware that this is /. right?
Many, if not most people here take apart stuff and find out how it works for fun. Why, just this weekend, I'll replace a radiator in my wife's van for a fourth of what the repair shop would charge, then later I might compile a new kernel or something. When I'm done, I'm probably gonna treat that old lawn mower to a new magneto, and then later, restart work on my control program for my radio scanner.

Re:any relation to the Ubuntu update?

[LingNoi]

Well most of the time when there are updates the changelog doesn't actually display any text and reads "unable to download changelog". Also, it was just a fucking question!

This post was brought to you by an elitist openbsd administrator

Figures, BSD trolls strike again..

Re:any relation to the Ubuntu update?

[CarpetShark]

Wrong. Updates in distro releases are usually security updates, which should be applied by everyone.

Re:any relation to the Ubuntu update?

[ion.simon.c]

I guess that OpenBSD doesn't have a decent package manager... Most package managers can figure out what packages are installed on a user's system, then only notify the user about updates to those installed packages. But, I suppose that *everything* is harder over in OpenBSD land.

Re:any relation to the Ubuntu update?

[DrSkwid]

Nope, they guy tries to *sound* elitist but isn't. OpenBSD uses Ports which was a package manager long before Ubuntu was on the scene.

I'm an elitist OpenBSD administrator too. I try to give us a bad name but usually with elitism not idiocy.

Re:any relation to the Ubuntu update?

[DrSkwid]

You don't know how a car works? And are happy about it! Perhaps you should stick to MacRumours not /.

Re:any relation to the Ubuntu update?

[ion.simon.c]

*grins* I was baiting the guy. I know about Ports. Gentoo's Portage was designed in its image. :D

subject

[cstdenis]

This is bad for all those who use DNSSEC. Both of them must be annoyed at the need to their software.

Re:subject

[Anonymous Coward]

I think he just accidentally the whole DNSSEC.

Re:subject

[AceofSpades19]

You mean there is another user?

Are we actually supposed to trust these people?

[mrsbrisby]

I don't have anything to add to my subject.

Yeah, um...

[Ethanol]

That's not a "DNS flaw".

It's an OpenSSL bug that turned out to affect BIND.

Re:Yeah, um...

[Anonymous Coward]

Since the Windows resolver can connect to BIND, and Microsoft didn't release a patch, a well-written Slashdot summary should have read

Microsoft refuses to fix critical Windows 7 security vulnerability.

Re:Yeah, um...

[Florian Weimer]

It's an OpenSSL bug that turned out to affect BIND.

No, it's a misuse of an OpenSSL API from within BIND, so the error is on BIND's side. It's of extremely low impact, though.

Re:Yeah, um...

[slash.duncan]

Exactly. I was just on the ISC site checking out something else (someone was asking about DNS for MS W2K and I was checking on that), and they said return codes for openSSL function calls weren't being checked in a few places so a verify failure may not have been properly caught. The released patch and downstream updates fix that.

time to dump BIND

[hansoloaf]

and go wtih djbdns

Re:time to dump BIND

[abigor]

Make that PowerDNS, and I agree. BIND is a flaming sack of dog shit, and the conflation of DNS with BIND in many people's minds drives me nuts.

Re:time to dump BIND

[morgan_greywolf]

Personally, I use ldapdns, which used to be based on the djbdns code and continues to adopt some ideas from djbdns, The nice thing about ldapdns, though, is that the database store is entirely in LDAP. You change it in LDAP and the changes in the DNS server are instantaneous.

I would consider PowerDNS as well, but ldapdns is also very small, fast and lightweight and it scales well. I don't get the feeling that PowerDNS is so lightweight.

Re:time to dump BIND

[abigor]

PowerDNS is actually quite light. They had the good sense to split it into a caching nameserver and a recursing resolver, making two lightweight daemons, rather than a single "does everything" process.

It's also nice because it can suck in BIND zone files if you're stuck with them and don't want to migrate. Good commercial support is also available. The code itself is GPL.

Re:time to dump BIND

[Morty]

It doesn't make sense to drop BIND in favor of djbdns just because of this. djbdns doesn't even try to do DNSSEC. The bug in BIND is not a direct attack on the DNS server, it just means that DNSSEC validation doesn't always work right. By switching from BIND to djbdns, you are completely breaking DNSSEC validation. In different terms, the worst consequence of this bug was that it sometimes made BIND act like djbdns.

Only if you're using BIND and DNSSEC

[billstewart]

Otherwise not a problem.

Re:Only if you're using BIND and DNSSEC

[hairyfeet]

Sorry, but while I appreciate the attempt, the program you gave doesn't work. It only supports XP Pro and crashes instantly in Win2K Pro. So does anybody else know of an easy to use DNS server for 2K Pro? Or am I just going to have to stick with Treewalk and hope I don't get hacked?

Re:Only if you're using BIND and DNSSEC

[slash.duncan]

I no longer do proprietaryware, so this isn't from personal experience. Point one is second hand and point two is based on the docs. Be kind to me mods, I did turn the karma bonus off and I am being transparent on the authority level.

1) Doesn't "Pro" at least come with a DNS server of some sort? I was under the impression... or maybe you don't trust it (you won't get any argument from me there, altho 2K was still respectable as it didn't yet have the eXPrivacy thing that was what ultimately gave me the final push I needed to jump to freedomware... thanks, MS!).

2) Good old BIND is available on MS platforms as well as *ix. It appears that the pre-built binary supports from XP/2003, but at least according to the documentation shipped with the sources, building for 2K is still supported. "Easy to use and setup" is of course relative, but the instructions for building from source are there. You may of course have to get gcc or the like if you don't have a decent compiler installed. (Some folks consider an OS that doesn't even ship a compiler as an install /option/ little more than a toy. YMMV.) FWIW, I'm running BIND here on Gentoo, of course compiled from source, self-configured after teaching myself how based on the documentation, so it's not /that/ hard. However, as I said, "easy" is relative and for platforms that don't come with more or less automated compile-from-source as a feature it'll certainly be somewhat more difficult. But it appears certainly doable and a quick google demonstrates there's additional resources out there for those on MS platforms (including 2K, which I included in my search terms) as well.

YMMV, and it's certainly understood if this doesn't meet your definition of "easy", but it appears to be both doable and supported so it's an option that's out there, at least. Even if you don't choose such options, it's nice to know they exist, just in case.

Re:Only if you're using BIND and DNSSEC

[MrCrassic]

This might not be of help, but while I don't know of any DNS servers for Win2K Pro/WinXP/WinVista, I'm pretty sure that their Server line comes with DNS services already available. After doing a Google search, this came up.

Good luck!

Re:Only if you're using BIND and DNSSEC

[hairyfeet]

Only works on Win2K and 2K3 server. The only one that does support non server OSes costs more for a license than my PC cost. And with the economy in the crapper I don't have the $$$ for a server and a license. There has to be a DNS server out there that works for Win2K Pro. I mean surely, as much software as there is out there, there just has to be! I guess I'll just have to keep running Treewalk and hope I don't get boned running a BIND-LE from 2005. Thanks anyway.

Re:Only if you're using BIND and DNSSEC

[hairyfeet]

Win2K Pro doesn't come with any DNS, and trying to compile using GCC on Win2K Pro is about as fun as getting hit in the nuts repeatedly with a ball peen hammer. Linux and Windows just don't play nice with each other, at least not for me. And all my gear doesn't work in Linux. The board has funky proprietary chips, the all in one printer won't even print, and the router won't talk to anything but IE for configuration. So switching to Linux is pretty much out. I need something I can fire up and walk away from.

I guess I'm just trapped running an easily hacked version of BIND-LE, which is what Treewalk is with some GUI tools. Because I've spent the past couple of days researching and have come up with squat. I just can't believe with as many Win2K Pro machines as there are that there isn't a single program to do what I need. So I appreciate the effort, but I've tried running GCC on Win2K Pro and all I got out at the end was a monster headache. Thanks anyway.

Re:Only if you're using BIND and DNSSEC

[slash.duncan]

> And all my gear doesn't work in Linux.

Been there. =:^(

Luckily, about time W98 (which I was in line for at midnight, after running the IE4 betas and installing IE4 with desktop enhancements on W95) came out, I started playing around with Linux, and soon began to require that any hardware I bought was Linux compatible, so by the time MS gave me that final shove when they decided eXPrivacy was going to require authentication, I had been buying all Linux compatible hardware for a couple years and was fine to switch. A shame for MS as I had spent some thousands on them over the years, but my gain, and now I'm glad MS did give me that final shove as after a decade on the platform I'm honestly not sure I'd have ever fully jumped if they didn't. But I wasn't going to authenticate, which left me the choice of turning to the dark side, or, fortunately for me, the bright side, no more middle-ground for me, and since then, with the exception of the nVidia drivers for my installed at the time video card (I didn't groke the difference between proprietary and freedomware Linux drivers before the switch, when I was buying all Linux compatible), which I upgraded to a freedomware compatible Radeon at the first opportunity, and one old DOS game I still play in DOSBOX, everything I run has been freedomware.

Re:Only if you're using BIND and DNSSEC

[hairyfeet]

Sigh.....that must really be nice to be able to do that. In the past 5 years I have spent exactly $0.00 for my PC gear. With a paraplegic sister and a half blind mom who had to quit working to take care of sis I just don't have it. Every dime that I make at the shop ends up going to them or my boys. So I have adapted and became a "scrap rat" to keep myself in gear.

A customer will come in and say "I hate this thing, it is too slow! Can you get my stuff off and get me a faster one?" or "This thing is broken! I need a new one" and I offer them a discount on my labor if they let me have the old gear for parts. I am currently looking at a 1.5GHz Athlon sitting across from me that I have to take to my engineering buddy down the hall to change out a bad cap on, which he is doing that and fixing a couple of broken wires on an external USB HDD in return for me doing a repair reinstall on his XP Pro work machine. That doesn't count the 2.6GHz Compaq I haven't had time to fool with or the 3.06GHz Celeron chip that I need a motherboard for.

So while I would love the freedom of building my entire network to my specs, it will simply never be. And this old 1.1GHz HP Pavilion I am typing this on has been running non stop(only turned off long enough to move) for 24/7/365 for the 9 years it has been since a customer brought it into my former repair job cursing WinME. It may be proprietary as hell, but this thing just keeps on going year after year, and with a stripped down Win2K Pro(which I got from my boss in return for putting in a little overtime) it makes a great Netbox. No noise, no heat to speak of, and very snappy. So while I keep saying with my next build that I'll finally put her down, I have yet to find anything as reliable, so there she sits. But good luck on your Linux journey. It must be nice to design everything just the way you want it....sigh.

Re:Only if you're using BIND and DNSSEC

[slash.duncan]

Well... if you look at my posting history, you'll note that I learned the hard way to actively prioritize things in my life, and then actively go after what I have prioritized.

In a way, you're lucky, in that you have family you value highly enough to make that sacrifice for. You mention both upstream and downstream family. I don't have any downstream family. I do have upstream, but while I love 'em, let's just say we get along better if there's a bit of distance between us. So I have no family to spend money on. I also don't have a car (I razor-scoot to work and the grocery and there's the bus), and as many geeks, I'm just as content spending a nite at home on the computer as out partying or whatever, so "having a life" isn't a priority either.

Really, the computer's pretty much my priority, and what I spend most of my money on. So yeah, I have a decent one (plus a netbook I got last year) tho I've sacrificed a bunch of other stuff to have it.

But you tell me. You obviously prioritize your family. I prioritize my computer. Would you honestly like to switch places, and not have that family to prioritize? Perhaps you would, but I'd guess there's a reason your sister and mom aren't wards of the state or whatever and you have them to look after instead of a decent computer. I can't honestly say I'd switch places with you either, but if I were close enough to my family to prioritize them as you obviously do yours, I expect I'd be singing a different tune. I'm reasonably happy with where I am in life, but I do realize some of the things I've given up to get there, and a decently close family either upstream or down is one of them. You have that. I don't. Realize what what's worth to you and treasure it. =:^) (Or conversely, grow a heart of stone, dump 'em on the state or let 'em fend for themselves, and go for what you DO want... but I have a feeling you already have it. =:^)

Meanwhile, now I really DO wish I had a decent DNS option for you. But somehow, I think you'll get by. You seem to appreciate what's REALLY important in your life, and somehow, those that do, do get by, and are happier despite trying circumstances than those that don't.

Re:Only if you're using BIND and DNSSEC

[Derek Pomery]

My computer is 8 years old AMD 1.4ghz - and yes, when I bought it, I checked the compatibility.
It would be interesting if you posted the actual hardware you are having issues with.
The problems may have been resolved.
An out of the box linux has far better HW compatibility these days than Windows.
The windows advantage is the manufacturers actually make sure the equipment has the drivers when they sell it to you.
If you build on your own, which, if you are as poor as you say, you should, you can trivially ensure compatibility and save money as well.

Re:Only if you're using BIND and DNSSEC

[hairyfeet]

I guess you didn't really read my post. i don't actually BUY hardly anything. I swap the machine off of a customer and then scavenge the pieces I need. So there isn't any "shopping for compatibility" there. As for the gear, well besides the Windows programs I use for work, There is an HP Pavilion with a funky as hell audio chipset(not realtek, that would be easy. Maybe an old Ali? I've not busted it open in awhile) along with a Trendnet router that only works with IE for configuration and a Lexmark x1270 all in one(good luck getting THAT to work).

While I have used Linux on an old laptop in the past with the way my setup is now I would have to build a machine JUST for Linux, and I just don't have the cash or the room for it. So while I'm glad that Linux works for you, for me it is a non starter. Nobody will pay me here for Learning or fixing Linux, all I need is a DNS app so it would be nuts to toss everything just for a single program, not to mention having to find dozens of new apps and learning to configure them to do what I need, and finally it would be crazy to toss a perfectly running machine just to run a new OS that won't run the programs I use anyway. And I can't afford to build a server just so I can run a Linux DNS, which is the only thing I'm lacking ATM. So I guess I'll be sticking with Treewalk and hoping I don't get hacked. Because I just don't have the time nor the money to start over just for a DNS server.

DNS Flaw?

[HairyCanary]

"DNS Flaw"? Can we shoot for a bit more accuracy here on Slashdot, since we're all technical enough to understand the details? It's a flaw that affects BIND. And BIND != DNS. I shouldn't have to point that out...

A: Because it breaks the flow of a message

[DNS-and-BIND]

Q: Why is starting a comment in the Subject: line annoying?

Re:A: Because it breaks the flow of a message

[b4dc0d3r]

DNS-and-BIND (461968) wrote:

Q: Why is starting a comment in the Subject: line annoying?

Did someone already hack you before you got this patch installed?

Why the sarcasm?

[MoeDrippins]

> Remember the big DNS flaw that Dan Kaminsky 'discovered' last year?

Why emphasize "discovered" in sarcastic quote marks? Did he NOT discover it? Was it someone else?

QEMU + more modern OS

[DrSkwid]

qemu.exe -hda debian.qcow -redir udp:53::53 -snapshot -vnc 3

then you can run whatever DNS server you like (not necessarily Linux - Plan 9's DNS server doesn't suffer the sequence number guessing problem). Use snapshot once it's set up so that you can just switch off without worrying about syncing its fs, (or use the console to apply fs changes while in snapshot mode). Or use samba to attach to the Host FS and use that, or use AOE (though I've only tried that the other way round with Linux as the host).

Ironically *we* use this setup to run our Windows 2000 server for the Win32 software we have to use (Movie Magic & Final Draft). The laptops start QEMU up on boot. My EeePC runs Qemu at usable speeds, even without the kernel module kqemu.ko.

Booting Windows locked down is a real boon. I don't have to worry about LAN based malware attacks etc. or failed updates / installs.

Hope this helps :)