With regard to the recent Patch Tuesday fix, there has been an issue fixed regarding NTLM Relaying, that has been around for more than eight years.

In 2000, I wrote an advisory about NTLM relaying (CVE-2000-0834). The problem turned out to be significantly larger than I originally suggested in the advisory. The attack extended to other NTLM-based authentications on other protocols and allowed general-purpose credential theft via a man-in-the-middle attack.

The SMBRelay tool was published in 2001 by Sir Dystic of Cult Of The Dead Cow, and that really took it to the next level. The protocol completely fell apart. It kicked off a number of other analyses of the NTLM protocol that finally resulted in this patch. Eight years after it’s discovery.

At least they got around to it. Thanks!

Assuming the mailbox hack is not an elaborate ruse, how did they do it?

Almost as bad as the Sprint PCS password reset fiasco that made the news in April, here is the Yahoo Mail password reset screen:

As you can see, you need to know the user’s birthday, country of residence, and postal code. Not difficult information to dig up in Palin’s case, as shown here. After you enter this information correctly, you are asked to type in the alternate e-mail address that’s associated with the account. But they give you hints — so if your alternate e-mail was sarah@alaska.gov, they would show you s****@a*****.gov.

Assuming you guess the alternate e-mail correctly, Yahoo mails a password reset link to that address. So it’s likely that the attacker may have also had to gain access to her alternate e-mail account. Either that, or they exploited a vulnerability in the Yahoo password reset mechanism itself, which seems less likely but not implausible.

So Yahoo itself probably didn’t get hacked, per se, even though there will probably be a lot of FUD in the media about that.

Update 08/18/2008 1:00am EST:

Just found this writeup describing how it transpired: http://pastebin.com/f7fb944c5. Again, not vouching for the authenticity but it does seem plausible, and it’s consistent with my password reset theory. I guess my Yahoo account doesn’t have a secret question defined so I wasn’t presented that option when I tested the reset mechanism earlier today.

Just for fun, here’s the list of non-customizable secret questions Yahoo lets you pick from, as of tonight:

And they sure don’t make it easy for you to update your secret question, do they? (must be logged in to Yahoo for that link to work)

A group of individuals has compromised VP candidate Sarah Palin’s personal email and sent the information to Wikileaks which has posted the information publicly.

http://wikileaks.org/wiki/Sarah_Palin_Yahoo_email_hack_2008

Alternate link (wikilieaks is down): http://cryptome.org/palin-email.zip

Circa midnight Tuesday the 16th of September (EST) Wikileaks’ sources loosely affiliated with the activist group ‘anonymous’ gained access to U.S. Republican Party Vice-presidential candidate Sarah Palin’s Yahoo email account gov.palin@yahoo.com. Governor Palin has come under criticism for using private email accounts to avoid government transparency mechanisms. The zip archive made available by Wikileaks contains screen shots of Palin’s inbox, example emails, address book and two family photos. The list of correspondence, together with the account name, appears to re-enforce the criticism.

Internet security has finally become an issue in presidential politics.

Palin’s use of a Yahoo account has been the subject of recent newspaper articles. The Washington Post published her Yahoo email address, which was likely a precursor to the attack.

Why bother setting up dedicated websites to host malicious content when you can just infect trusted sites like BusinessWeek? This is becoming something of a trend, as evidenced by the mass SQL Injection attacks from a few months ago.

The idea is simple — find SQL Injection vulnerabilities in high-traffic, trusted websites where the site’s content is dynamically fetched from a database (i.e. just about any content-rich site). Then use an automated tool to prepend or append malicious content to that content in the database. When the unsuspecting user visits the page to read an article, they will be treated to a barrage of <script> or other tags fetching content from sites in .ru, .cn, or who knows where else.

The guidance you give to mom and dad, “don’t visit sketchy looking sites in other countries,” is no longer good enough. If BusinessWeek can be compromised, it’s a given that USA Today, CNN, the New York Times, and other establishments are being targeted as well.

For this and similar examples, NoScript would have thwarted the attack because it wouldn’t permit the .js file to be loaded from an off-domain location. But what happens when the attackers start injecting the entire .js payload into the database instead of just a <script> tag? Now the malicious code is coming from the trusted domain, and if I’ve configured NoScript to allow scripts from businessweek.com, I’m out of luck. In fact, I have no idea why the attackers aren’t using this tactic already. Any ideas?

Earlier today, the US District Court dealt a victory to the MBTA hackers and the EFF, lifting the injunction issued on August 9th to prevent the three MIT students from presenting their findings at DEFCON 16. In summary:

The lawsuit claimed that the students’ planned presentation would violate the Computer Fraud and Abuse Act (CFAA) by enabling others to defraud the MBTA of transit fares. A different federal judge, meeting in a special Saturday session, ordered the trio not to disclose for ten days any information that could be used by others to get free subway rides.

“The judge today correctly found that it was unlikely that the CFAA would apply to security researchers giving an academic talk,” said EFF Staff Attorney Marcia Hofmann. “A presentation at a security conference is not some sort of computer intrusion. It’s protected speech and vital to the free flow of information about computer security vulnerabilities. Silencing researchers does not improve security — the vulnerability was there before the students discovered it and would remain in place regardless of whether the students publicly discussed it or not.”

This sets a good precedent for future cases, and perhaps next time a similar situation arises, a judge will not be so quick to issue a gag order. It’s not a happy ending yet though, as the original lawsuit is still in effect.

As Chris Wysopal pointed out last week, the MBTA’s ire is misdirected. Rather than suing the vendor who sold them the defective system, they sued and attempted to silence the students who discovered the weakness. This is 2008, not 1988 — did they honestly think a gag order would prevent the information from reaching the general public? The DEFCON presentation was already available on the Intertubes prior to the injunction being issued, and the MBTA attorneys included a copy of the confidential whitepaper with their filing, thereby making it public.

I guess you wouldn’t expect that a transit authority would have paid any attention to the Ciscogate fiasco from a few years ago. That presentation never got out either, did it? All that taxpayer money the MBTA spent on ridiculous lawsuits and restraining orders could have been put toward fixing the security flaws. What a concept.

By now, you probably know that details of the DNS vulnerability have leaked. Halvar Flake speculated on DailyDave and the momentum built from there, despite the fact that his guess was short on a few key details. I don’t need to rehash the full technical details here; by now, they are easy enough to find with a couple Google searches. When Slashdot picks up the story, it’s hardly a secret any more.

What’s more interesting to me, now that I’ve digested the big secret, is how this whole situation has played out in the security community.

The security community has been polarized for the past two weeks, not so much over the technical details being withheld, but about Dan’s plea that people not speculate about the vulnerability. As many pointed out, the “bad guys” won’t stop trying to figure it out just because the “good guys” keep quiet. To be honest, my own lack of public speculation wasn’t because I agreed with the philosophy; I just wasn’t smart enough to figure out the vulnerability myself.

People implied — or stated outright — that Dan just didn’t want anyone stealing his thunder. Considering the timing of the release and the subsequent BlackHat talk, it’s obvious why such accusations were made. Personally, I think it’s a little of each. I believe the coordinated patch effort was undertaken with the best of intentions, but I also think Dan relished some of the glory and media attention as well. It’s hard to blame him for that; if you were in his shoes, wouldn’t you want some recognition too?

By many accounts, dealing with the DNS vulnerability from the operational side has been an exercise in frustration. Plenty of IT people wanted to patch but couldn’t get approval without being able to justify the operational risk. “Because Dan said so” is apparently not a convincing enough argument. Some wondered why the people who were responsible for creating the problem should be blindly trusted to implement an appropriate fix?

Ultimately, vulnerability disclosure is a minefield. No matter how you choose to disclose, somebody will always disagree.

P.S. If you didn’t figure out the title of the post by now, Nate was one of the unlucky few to draw the same timeslot at BlackHat as Dan Kaminsky.

A co-worker passed along this snapshot taken at the Karsten Nohl, Jake Appelbaum, and Dino Dai Zovi talk at HOPE this past weekend. The context, of course, is that the overzealous Debian developer who accidentally crippled OpenSSL back in 2006 said he did so because valgrind reported uninitialized memory use. Click through for the full-size version.

So automated software review is dangerous now? Perhaps that bullet should read “modifying code you don’t understand is dangerous.”

The security community is cynical. So much so, that most of the chatter that’s taken place over the past 24-36 hours has suggested that Kaminsky’s DNS vulnerability was little more than a publicity stunt and that his BlackHat presentation would be an over-hyped rehash of prior art. Granted, one has to suspend disbelief to even consider that something monumental would be discovered in DNS — that’s the protocol itself — but hell, it’s always nice to give a guy the benefit of the doubt.

Faced with nearly a month of criticism and questioning, and understanding the persuasive power of a technical peer review, Dan decided to expand the inner circle, so to speak. Rich Mogull arranged a phone call with Tom Ptacek and Dino Dai Zovi so that Dan could spill the beans and let them decide for themselves whether it was spin or substance. Turns out there was substance.

Now we sit around and wait until August 6th to cram into a ballroom with a thousand sweaty conference-goers to hear the juicy details. And Dan’s presentations are usually packed to the brim even when he’s not announcing anything.

In the meantime… how about patching those servers?

Rich Mogull’s executive overview of Dan Kaminsky’s latest DNS vulnerability fluffed a few feathers yesterday:

The good news is that due to the nature of this problem, it is extremely difficult to determine the vulnerability merely by analyzing the patches; a common technique malicious individuals use to figure out security weaknesses.

The typical response I heard was “what do you mean, it can’t be reverse engineered? I’ll just look at the diffs!”

In hindsight, after examining the BIND diffs (yes, I did it too) and discussing with colleagues, all most people saw was UDP source port randomization and a better PRNG for generating the transaction ID, the latter of which would appear to be related to Amit Klein’s cache poisoning attack from about a year ago.

What Rich was really saying is that you can reverse engineer the patch until you’re blue in the face, but that won’t reveal the specifics of the vulnerability.

Dan’s blog post this morning appeared to confirm that interpretation:

DJB was right. All those years ago, Dan J. Bernstein was right: Source Port Randomization should be standard on every name server in production use.

There is a fantastic quote that guides a lot of the work I do: Luck is the residue of design. Dan Bernstein is a notably lucky programmer, and that’s no accident. The professor lives and breathes systems engineering in a way that my hackish code aspires to one day experience. DJB got “lucky” here — he ended up defending himself against an attack he almost certainly never encountered.

Such is the mark of excellent design. Excellent design protects you against things you don’t have any information about. And so we are deploying this excellent design to provide no information.

To translate the fix strategy into a more familiar domain, imagine large chunks of Windows RPC went from Anonymous to Authenticated User only, or even all the way to Admin Only. Or wait, just remember Windows XPSP2 :) This is a sledgehammer, by design. It cuts off attack surface, without necessarily saying why. Astonishingly subtle bugs can be easily hidden, or even rendered irrelevant, by a suitably blunt fix.

Nate McFeters appears to think that Tom Ptacek has figured it out. I’m going to go out on a limb and say that Tom didn’t figure anything out yet but still wanted to write a pithy blog post. I think that if Tom had figured it out, he would have written it down privately and posted the SHA-1 hash, as is the trendy thing to do these days.

Speculation aside, the title of Tom’s blog entry, Dan Kaminsky could have made hundreds of thousands of dollars with this DNS flaw!, does make an important point — Dan didn’t sell the details to ZDI, he used his influence and reputation to coordinate a massive vendor patch effort. That’s an admirable move.

We all know it happens, but it is rarely exposed as clearly as Adam Pennenberg did in his article for Fast Company, The Black Market Code Industry. It turns out that this 0day seller was an HP employee:

According to the consultant who snared Marester, his quarry’s skills appear quite sophisticated. His wares, if they performed as advertised, could help a hacker take down machines running that particular software anywhere in the world. His real name is Steve Rigano; he’s a self-employed network consultant from Grenoble, France, who works full time at HP, where he is listed in the switchboard and maintains an hp.com email address. He told me that he saw nothing wrong with offering tools and techniques that targeted the company providing his paycheck.

A self-taught hacker, Rigano says he discovered the vulnerabilities and coded the exploits on his own time, which he says is none of HP’s business. “I have the right to sell what I want,” he says. He told me he attracted mostly Chinese and Russian buyers, but claimed he never found takers for the HP or SAP “vulns” and exploits. He said he stopped selling black-market code in January but didn’t explain why.

Most security companies I have been acquainted with frown on this type of activity, as I am sure HP has. It’s hard for them to sell security products and services when their employees are selling the very tools the company is purportedly defending against.

[Update 7/7/2008: The information in the Fast Company article is being disputed by Steve Rigano. He has notified us that he has taken legal action against Adam Pennenberg and Fast Company.]