Slashdot Mirror
Microsoft Admits XP Has Same Bug As Win2K
Arashtamere sends in a Computerworld story on a security flaw in the Windows 2000 pseudo-random number generator published by Israeli researchers earlier this month. Microsoft has now admitted that the flaw is present in XP too. Microsoft denies that the bug is a security vulnerability, since an attacker would have to have gained administrative access to a system before exploiting it. (The Israeli researchers point out that many common exploits provide admin access.) This stance apparently lets them off the hook for patching Win2K, which is in "extended support" mode, though it powers about 9% of US and EU business computers. Microsoft said that XP SP3, due in the first half of next year, will fix the bug. The company said that Vista, Windows Server 2003 SP2, and the new Windows Server 2008 are not vulnerable.
if you already have admin access via another "exploit" why would you bother attacking via random number generator, seems like its a lot of fuss over nothing, Windows has alwayss been vunerable locally (luckily for admins whose users forget passwords etc) so the most worry is over a remote exploit which this flaw isnt. But iam sure some million dollar company will sell a solution for this, paranoia is a great sales tool in the murky world of snake oil, cough i mean computer security
If you have admin access, the battle's already lost. What's the point of running a complex process to obtain their password when you have full access to everything on their computer? Might as well just drop in a keylogger and get the same info much easier.
Comment of the year
A reason to upgrade to Vista! ;)
Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
This article refers to this summary of this paper
I fail to see why you would need administative privelidges however. You would only need to run in the userspace of the process that did run the random number generator before. Having administrative privs would be nice to inject code into that userspace, but is not needed i think.
It can get even worse if from a public key part the random number that was used to generate it can be extracted, what was done in early ssl implementation attacks.
Here is the original article on the ACM.
Very brief summary of article
Each process has their own instance of the generator, and the refresh of the internal state is done after 128 kbs of output from the generator (roughly 600-1200 SSL connections with IE). Not only that, it is run in the userspace so it is not a security violation to examine the internal state of the generator. The function used is not one-way which provides a means looking at past transactions of a user (within the 128 kbs of data).
Lack of planning on your part does not constitute an emergency on mine.
Microsoft claims this is not a "security vulnerability" because the machine has to already have been cracked to exploit it.
That is not 100% correct.
It is still a "security vulnerability".
It just cannot be exploited to increase your access on that machine.
That we know of. Today. So the code still needs to be patched. Security is not an "either / or" situation. You have to reduce the effectiveness of threats.
While in general I think open-source and closed-source software can coexist, I think this is a pretty good example of why anything related to crypto should be open. All of public key cryptography relies on the secrecy of private keys, not on the secrecy of the algorithm itself. And while they might have faithfully implemented the algorithm, who knows what kinds of arguments/whatever to the crypto functions might cause undesired results -- it's just too hard to test.
In any case, the thing that surprised me most from the article was that Windows 2000 users would be left out in the cold: "Because the company has determined that the PRNG problem is not a security vulnerability, it is unlikely to provide a patch [for Win2K]." Wow. Especially when it's something this easy to fix. This bug also solves any attacker's problem of trying to sort valuable from non-valuable information, since presumably any valuable information (credit cards used online, etc) will use encryption. And while someone suggested that a program should use its own random number generator, there is a problem because, in general, your application (not running as Admin) shouldn't have access to nearly the same amount of entropy sources (like network activity, GUI inputs, etc).
--
Educational microcontroller kits for the digital generation -- great gift!
It's flamebait because the GP didn't have to call people retarded, in order to get his or her point across.
They also could have worded this a lot more diplomatically than they did. So yes, the GP is flamebait.
No tyrant thrives when every subject says no.
Thanks for the flashback to l0pht's old page....! For those who don't remember it before it got rolled into @stake:
"'That vulnerability is entirely theoretical.'-- Microsoft;L0pht, making the theoretical practical since 1992."
Don't tell me to get a life. I'm a gamer; I have LOTS of lives!
Possibly. What would be better still is to show, provably that those he was calling morons/idiots, were indeed morons/idiots. As it is, he just insulted all slashdotters (including me, obviously), many of whom are not either.
No tyrant thrives when every subject says no.
Microsoft Admits XP Has Same Bug As Win2K
More correctly, "Microsoft Admits XP has same bugs as Win2K."
The higher the technology, the sharper that two-edged sword.
>Microsoft said that XP SP3, due in the first half of next year, will fix the bug.
It should be an offence to know and state you know about a bug but sit on the fix for months. This is a really stupid MS position and will push people more towards alternatives like GNU/Linux.
It should be a hot fix right now.
Meanwhile, free/libre open-source unices like Linux and *BSD have been having a sound random generator that doesn't suck too much for, like, ages...
No, sorry, you can keep Vista for yourself.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
One concrete weakness of this attack is that it permits you to reverse-engineer "secure" sessions _before_ you got admin privilege, as the random number generator can be 'rewound'.
:-) ) is an important trait, and MS's scheme is missing it.
So-called forward security (yes, looking at things in the past is 'forward'
Also FatPhil on SoylentNews, id 863
No worries about whether or not it's even legal to fix a machine that I'm using to run my business.
Free Software: Like love, it grows best when given away.
Hell no, but the onus of proof is not on me :) I'm not the one accusing.
No tyrant thrives when every subject says no.
And your "random"-number generator, unless based on a proven algorithm, might well have vulnerabilities of its own to worry about. If you keep the source code secret, no serious security person is going to touch it with a barge pole; and if you show the source code, then your extra layer is largely irrelevant since the sequence only depends on a seed supplied by Microsoft's PRNG.
The nub of the problem is that a deterministic state machine can never produce random behaviour. The long term solution would be an entropy generator on the motherboard. (Actually, many machines have one already: a sound card with an unconnected high-impedance input picking up static is a good entropy source.)
Je fume. Tu fumes. Nous fûmes!
Knowing someone's password can be handy. Most folks use the same password on multiple machines or entire networks. Moreover they seldom change them.
Some drink at the fountain of knowledge. Others just gargle.
CryptGenRandom is supposed to be the Windows-equivalent of /dev/urandom. Except it's not, because of this design flaw. The implications of this extend far beyond encrypted NTFS volumes.
For example, an attacker can passively monitor a network of Windows machines, wait for one of them to do something interesting (like connect via SSL www.paypal.com), then actively compromise those selected machines later, and gain enough information to decrypt the captured SSL sessions.
Basically, if you encrypt something sensitive, before some spyware gets installed on your Windows machine---or after it's removed---the random data used for the encryption (including stuff like SSH session keys) is likely to be compromised (except perhaps in cases where you've rebooted or restarted the requisite processes in the meantime).
Do not underestimate the severity of this bug.
http://outcampaign.org/