Microsoft Tries To Censor Bing Vulnerability 275
An anonymous reader writes "Microsoft's Bing search engine has a vulnerability with its cash-back promotion, which impacts both merchants and customers. In traditional Microsoft fashion, the company has responded to the author of the breaking Bing cash-back exploit with a cease & desist letter, rather than by fixing the underlying security problem. It is possible for a malicious user to create fake Bing cash-back requests, resulting in not only fake cash-back costs for the merchant, but also blocking legitimate customers from receiving their cash-back from Bing. The original post is currently available in Bing's cache, although perhaps not for long. But no worries, the author makes it clear that the exploit should be painfully obvious to anyone who reads the Bing cash-back SDK."
And now thanks to /. and microsoft (Score:5, Insightful)
it will probably be all over the rest of the internet and general common knowledge within the week.
Re:And now thanks to /. and microsoft (Score:5, Funny)
~Barbara
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Just wait for it.
-Barbra
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I just read the Cease-and-desist letter. The proper response to such a thing is to tell the lawyer to "fuck off".
But of course that would merely result in you being drug into court by that lawyer.
Freedom of speech is dead.
Corporations own us. Don't believe me?
Go watch the documentary Food Inc (especially the last half hour).
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Re: (Score:2, Interesting)
it will probably be all over the rest of the internet and general common knowledge within the week.
The way you phrased this, it would seem to indicate that you are against slashdot for releasing this information. I fail to see how releasing this type of information is a bad thing. You would be better off believing in fairies than thinking only 1 person will find a way to exploit a bug. The more people who know about this issue the better as it will be more likely that microsoft will actually fix the bug instead of suppressing the author.
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The phrasing seemed pretty neutral to me. How would you have phrased it so that it doesn't seem to indicate that it is a bad thing?
Re:And now thanks to /. and microsoft (Score:5, Insightful)
GP just wants someone to hate on, you don't get much more neutral in phrasing than that without making a two word post saying only "Streisand effect."
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No, you get more neutral in tone by not blaming /. as you did in the title. If you had simply said "And now it will be all over the net." That would be neutral. However, you specifically chose to call out Slashdot and Microsoft as responsible for the Streisand Effect.
Slashdot is running the story that Microsoft is trying to hide. Therefore they are in fact RESPONSIBLE.
You are an idiot and need to STFU and go away for the day.
I'm not interested in fixing the bug... (Score:2)
Just interested in keeping the extra income 8)
Re:And now thanks to /. and microsoft (Score:5, Informative)
like this you mean?
Breaking Bing Cashback
Posted November 4th, 2009 by Samir
I've never bought anything using Bing Cashback, but the balance of my account is $2080.06. Apparently, I placed two $1 orders on January 24th of this year, and spent another $104,000 on October 24th. Let's see how these transactions might have "accidentally" got credited to my account.
First, we need to try to figure out how transactions get into Bing Cashback. Microsoft posted some documentation here. The explanation of how a merchant reports transactions to Bing starts on page 20. Merchants have a few options for reporting, but Bing suggests using a tracking pixel. Basically, the merchant adds a tracking pixel to their order confirmation page, which will report the the transaction details back to Bing. The request for the tracking pixel looks something like this:
https://ssl.search.live.com/cashback/pixel/index [live.com]?
jftid=0&jfoid=&jfmid=
&m[0]=&p[0]=&q[0]=
This implementation, while easy for the merchant, has an obvious flaw. Anyone can simulate the tracking pixel requests, and post fake transactions to Bing. I'm not going to explain exactly how to generate the fake requests so that they actually post, but it's not complicated. Bing doesn't seem to be able to detect these fake transactions, at least not right away. The six cents I earned in January have "cleared," and I'm guessing the remaining $2080 will clear on schedule, unless there is some manual intervention.
Even if Bing detects these fake transactions at some point in the future, the current implementation might have another interesting side effect. I haven't done enough work to say it with confidence, but a malicious user might be able to block another user's legitimate purchases from being reported correctly by Bing (I only tried this once, but it seemed to work). Posting a transaction to Bing requires sending them an order ID in the request. Bing performs a reasonable sanity check on the order ID, and will not post a transaction that repeats a previously reported order ID. When a store uses predictable order ID's (e.g. sequential), a malicious user can "use up" all the future order ID's, and cause legitimate transactions to be ignored. Reporting would be effectively down for days, causing a customer service nightmare for both Bing and the merchant.
Based on what I've found, I wouldn't implement Bing Cashback if I were a merchant. And, as an end user and bargain hunter, it does not seem smart to rely on Bing Cashback for savings. In our next blog post, I'll demonstrate some other subtle but important reasons to avoid using Bing Cashback.
Re:And now thanks to /. and microsoft (Score:5, Insightful)
Financial transactions based on a tracking pixel? Really? I just don't know where to start to point out how wrong that is.
PayPal has dozens of different ways to pay, and most of them suck, but at least they don't encourage people to rely on tracking pixels. Either you explicitly send the customer to the payment gateway (including login or entering credit card info there) to authorize the transaction, or you have your own server talk directly to the payment gateway. Relying on a hidden browser-side hack for a financial transaction is just amazingly stupid and unnecessary, even if you don't spot any obvious flaws right away (because someone else will).
Re:And now thanks to /. and microsoft (Score:5, Interesting)
And people often do precisely that for affiliate programs. Is it any wonder these programs make up one of the shadier areas of the internet?
Re:And now thanks to /. and microsoft (Score:5, Insightful)
In traditional Microsoft fashion, the company has responded to the author of the breaking bing cashback expoit with a cease & desist letter, rather than by fixing the underlying security problem.
Maybe they are doing both?
The cease and desist letter seems partially reasonable:
Specifically, at this site you are providing information directing users how to misuse the microsoft Bing Cashback program through unauthorized technical means. Further, on this website you admit that you have personally misused the Cashback program in this regard.
It's pretty stupid to admit you violate a law on a blog that has your name on it. He should have used a anonymous blog for that or inform Microsoft of the issue in the first place.
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Your comment about the "bloody knife in your hand" reminds me of a recent case in Baltimore. A man was presumed guilty and spent over 20 years in jail, because he was at the scene of the crime, and he *looked* guilty. But then a test was performed, and it was discovered that the DNA left-behind by the murderer (on the knife) was not the man in prison. Baltimore had caused an innocent man to lose 20+ years of his life.
This type of thing happens a LOT. We shouldn't be presuming guilt. We should be presum
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Perkins: Oh, your lawyer now, yes sir. Don't you think that might be a bit
of a waste of money, sir.
Edmund: Not when he's the finest mind in English legal history. Ever heard
of Bob Mattingburg?
Perkins: Oh, yes indeed, sir! A most gifted gentleman!
Edmund: I remember Mattingburg's most famous case, the case of the bloody knife.
A man was found next to a murdured body, he had the
Re:And now thanks to /. and microsoft (Score:4, Insightful)
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This is pretty clearly about disclosing a vulnerability, not "bragging" about defrauding a large corporation.
That doesn't change the fact that he did indeed defraud Microsoft and that he also intended to do it. That's something he could easily get convicted on. It doesn't really matter why he defrauded them, if he did so and intended to then he's guilty of the crime.
Re:And now thanks to /. and microsoft (Score:5, Insightful)
Wow, I didn't realize that there are people that still believe in that 'security through obscurity' nonsense.
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Wow, I didn't realize that there are people that still believe in that 'security through obscurity' nonsense.
For all we know, the OP is a proponent of that 'responsible disclosure' nonsense.
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Wow, I didn't realize that there are people that still believe in that 'security through obscurity' nonsense.
It's not nonsense, it's just silly to expect it to be your only line of defense. By all means use an obscure platform, as long as you have people who can maintain and support it, but don't use it as a substitute for some common sense, and for securing your system, keeping it properly maintained and updated, limiting points of entry, blocking remote root access, using non-standard, non-root usernames with very secure passwords for system maintenance/root tasks, etc..
But security through obscurity does still
Re:And now thanks to /. and microsoft (Score:5, Insightful)
I'm not sure how this is a sensible response to a poster complaining about security through obscurity: security through obscurity is exactly the problem here. We use information like SSN and address which are not in any way secret, merely obscure, as a way to supposedly verify identity, and that's why we have so much identity theft. The reason no-one wants to post their SSN and address on Slashdot is precisely because security through obscurity sucks.
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Re:And now thanks to /. and microsoft (Score:5, Informative)
Security through obscurity [wikipedia.org] is not about relying on secrecy of data, but about relying on secrecy of the algorithm or implementation. Those two things are different.
If you do not make the distinction between data/information secrecy and design/algorithm/protocol/implementation secrecy, then you do not understand what security is.
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I know Google has its detractors, but surely no more than Microsoft. We can't all be Steve Ballmer...
Re:And now thanks to /. and microsoft (Score:4, Informative)
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I keep an IE window open at work for the sake of an additional gmail account.
Sometimes I accidentally use its search box over Fire Fox's, and yuck, nobody will like it.
The results are so haphazard, it feels like their parody of google is what actually drives Bing.
I don't know how this late in the game a search engine can be so bad.
Re:And now thanks to /. and microsoft (Score:5, Funny)
The results are so haphazard, it feels like their parody of google is what actually drives Bing.
I don't know how this late in the game a search engine can be so bad.
answer:
Because
:D
It's
Not
Google
It's all in the name
Re:And now thanks to /. and microsoft (Score:5, Funny)
Bing
Is
Not
Google
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CashBack? Last Christmas Live cashback was up to 30%. I milked the hell out of that for Christmas presents.
Now it fluctuates between 5 and 10%, nothing big but it's not bad.
As far as actually using it for its intended purpose, nah.
How does he know MS isn't doing anything else? (Score:5, Insightful)
No (Score:5, Insightful)
If you have a glaring vulnerability that lets people defraud your customers out of arbitrary amounts of money, the only sane thing to do is immediately disable the feature. Not wait for a solution. Not cover up the issue. You make coverage of the issue irrelevant. If one person figured it out and wrote about it, 100 other people also figured it out and are using it for personal gain.
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Its possible that a workable solution could take some time to get implemented, and in that time, doesn't it make sense to send a C&D letter in the interim? Hell, doesn't it make sense to send the letter anyways, so you don't have all these assholes trying to break your system?
How the hell does a C&D prevent assholes from breaking your system? Only fixing your system can do that. They should have sent him a letter expressing their gratitude for pointing out this security hole.
But more than that, they shouldn't have enabled and encouraged merchants to rely on a horribly insecure payment method.
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I'm curious how 'anonymous reader' knows that Microsoft is doing nothing to fix the problem. This has been bugging me for a long time. Its possible that a workable solution could take some time to get implemented, and in that time, doesn't it make sense to send a C&D letter in the interim? Hell, doesn't it make sense to send the letter anyways, so you don't have all these assholes trying to break your system?
A C&D letter doesn't mean that other actions haven't been taken. Just a thought.
Obviously it's implied. But I think it's a reasonable implication.
1) If it was identified already as a problem on Microsoft's side, I don't think they would've gone through all the work to build the system as such. Their documentation indicated that this is how they suggest you setup your transaction. That tells me they thought they had a complete implementation and design.
2) Is there any indication in the C&D that corrective measures are being taken (other than squelching the whistle-blower)?
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Uh? Cash back is negative income for Microsoft, and as a lawyer who sends C&Ds for a living, I am offended by the fact that you call that "doing nothing".
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You're right, sending C&Ds isn't doing nothing.
It's actively producing negative work, turning productively spent time into wasted time.
So congratulations, you're doing less than nothing!
Re:How does he know MS isn't doing anything else? (Score:4, Insightful)
and as a lawyer who sends C&Ds for a living...
Wow, that's sad. That's almost like admitting to being a parking inspector...
Parking inspectors do important work. They keep parking spaces available for those who really need them. I feel sorry for the abuse they sometimes get.
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Simultaneously, they keep the taxes down for those of us that pay the meter.
Re:How does he know MS isn't doing anything else? (Score:4, Interesting)
I've had to fight parking tickets in court, though, because they were unjustly given... If the parking space says, for example, that street parking is allowed until 4:00pm, and they write a ticket that's dated 4:01, then it's unreasonable... around here, they're supposed to give you 5 minutes' leeway to allow for differences in how your watch is set. (that's actually in the law in this part of the world).
Worse still is the time I was given a $300 parking ticket because the jackass who wrote it was more concerned with meeting his quota than he was looking for the accessible parking permit that was clearly displayed on the dashboard... at least, it was clearly displayed until your view of it was blocked by the parking ticket that the idiot put, quite literally, on top of the accessible parking permit. The ticket wasn't for going over time, it was because my car was parked in a handicapped spot, and he hadn't noticed the permit. That one was resolved by a trip to city hall with both the permit and the ticket, but I shouldn't have had to take an afternoon off work because of a blind parking warden.
I fully agree that parking inspectors do actually do some important work. And I accept that most of them are just trying to do an honest day's work, and trying to actually perform a civic service. But some of the parking wardens are clearly becoming jaded at being the furries of the law-enforcement community, and are taking it out on people by power tripping.
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You obviously haven't seen parking inspectors or clampers in the UK at work.
Re:How does he know MS isn't doing anything else? (Score:5, Interesting)
I wrote parking tickets as a job in college... very easy. My rule was to let people go if they showed up during the ticketing, which resolves every single confrontation in a positive way. If I had to call a tow truck on the car, I had to stand my ground, but only once did I encounter someone who showed up during the process and was a real dick about it.
The parking services was second only to tuition and the football team in amount of revenue generated for the school. If anything, I could write more tickets by letting the few people I encountered during my work go and moving on to the 98% of cars whose owners don't show up rather than wasting 20 minutes arguing with each of them.
Easily the least stressful job I've ever had.
Re:How does he know MS isn't doing anything else? (Score:5, Insightful)
Re:How does he know MS isn't doing anything else? (Score:5, Insightful)
Ever heard of the Streisand effect? If you're trying to suppress information about something a C&D is the last thing you want to do. Furthermore many companies when put in an identical situation will respond with "Thank you we are aware of the problem and are currently working on it" rather then a C&D.
Also you sound like a schizophrenic jackass.
Re:How does he know MS isn't doing anything else? (Score:4, Insightful)
C&Ds do work in two cases:
The first is if the C&D gets out fast enough that people are not unable to mirror the information, especially if it is stored in a dynamic database that can't just be grabbed completely with a wget. One example of this: Say someone makes a keygen app that runs on their webserver, and people submit forms to get bogus serial numbers. A C&D would completely smash this, preventing the information from getting released. Similar if people ran other services that could be nailed by an ACTA or DMCA takedown notice.
The second is that the information that does escape the C&Ds gets pushed from mainstream sites to the seedy corners of the Internet. These are the same areas that have the dubious filesharing programs, the warez "search engines" and "DDL" sites [1], the "bump all Abloy locks in 2 secs, lulz" [2] text files, and other dodgy sites which tend to be more of a test of browser security than a place to find anything useful. So, unless someone is willing to spend time looking for that exact information on a hardened computer, it effectively has vanished.
Don't underestimate the power of lawyers. They have the guys with guns on their side.
[1]: I have DDL, or direct download in quotes because I have yet to personally see a usable direct download other than a Trojan or a drive by browser exploit in all my years of cleaning malware off of people's PCs who do believe in such fantasies.
[2]: Yes, I know Abloy locks are unbumpable because of their design, but it is a good example. I don't know anything that defeats their latest PROTEC line of locks other than 12-14 hours of painstaking picking by dedicated speedpickers, or a good long session drilling the sucker out.
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I doubt the soundness of thought of your second position as well. You actually allude to the weakness yourself, but to expand it, just because yo
Re:How does he know MS isn't doing anything else? (Score:5, Interesting)
Problem is, sending a C&D letter is doubly ineffective:
In fact, compare that to the way the last TLS-related vulnerability was handled; in both cases, a critical flaw is revealed before a fix was ready. In the TLS case, it was handled with forthcoming and transparency. I'm not saying that MS should do the same (MS probably can't); but they would show more respect to Samir, and to all their bing cashback clients, by:
Re:How does he know MS isn't doing anything else? (Score:4, Insightful)
As to your first point, most business are very secrative about potentially damaging things. I don't understand why it's surprising when MS acts just like every other large corporation in protecting itself.
It's a truism, if not a cliche, to point out business are secretive about potentially damaging things.
The difference here is that the scope of damage extends outside narrow corporate concerns. In such situations, it's both fair and reasonable for customers to expect a certain level of transparency. In many industries, disclosures that negatively affect third parties are mandated by law (cue the car analogies).
Microsoft has chosen, in historically typical fashion, the complete opposite of transparency. The criticisms are well deserved.
Re:How does he know MS isn't doing anything else? (Score:4, Interesting)
it's the lack of thought for consequences of censorship that has me confused. in this day and age, with the overwhelming occurrences of embarrassment that occurs repeatedly over censorship attempts and cover-up attempts, surely businesses would work out by now that a "thank you! we'll fix this IMMEDIATELY! and we'll even pay you some money, and, for anyone else who is listening, we'll pay a BOUNTY to anyone else who privately reports security problems in the future!" approach would make them appear to be a much more enlightened and responsible company. ... or am i just expecting too much?
.
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This reminds me of Warbird Adventures, an outfit here in FL that offered "experience" flights in WWII era trainers.
Back in 2005, one of their aircraft broke apart in flight and instructor and student were both killed.
Did they even post a tiny memorial on the site? Nope. Bad for business. But the disrespect shown for their former employee and customer was enough to keep me from ever recommending them again.
A little sympathy goes a long way towards a good reputation. The world isn't perfect, and there's no wa
Mirror (Score:5, Informative)
It seems like people have still not learned to never trust anything from the user. This reminds me of some trivially exploitable web merchants years ago. The would store the entire shopping basket, including prices, in the user's cookies. User simply modifies their cookies so that everything costs $1 or $0.01 and they could order a dozen cpus / t-shirts / whatever for a few bucks.
Re:Mirror (Score:5, Insightful)
Also the guy who posted this is an idiot for placing a $100,000 transaction which would result in a $2,000 payment, and then bragging about it. His two $1 transactions proved the vulnerability and the $0.06 payment generated is easily ignored. The $100k transaction with $2k payment is just flat out wire fraud asking for federal PMITA prison.
Why is this troll? (Score:2)
Seems pretty spot-on to me.
Re:Mirror (Score:5, Insightful)
Parent is not a troll. This guy is seriously in for it - the FBI et.al frowns upon people who cheat companies out of literally thousands of dollars. The six cents would've been overlooked, and prove the point nicely.
$2k will certainly not be overlooked. Even if he never collects it... he's still fucked.
How is this a cheat? (Score:2, Insightful)
This is no more a cheat than taking someone's money for a shell game and showing them afterwards how they were scammed.
If he's said "by the way, I managed to get 20 grand off you by this" then he's not defrauded them. If he'd kept quiet THEN he'd have defrauded them.
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This guy has been seriously stupid. Not only is it clearly fraud, he's also up for conspiracy to defraud charges for telling other people how to do this.
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No, six cents does not prove a damned thing. There might be code in there to flag "high transactions" for further checks. They KNOW their system is insecure and could put that in there to deal with the less common riskier cases. THIS is a test to see if people can steal more than a few cents. That's what counts. If a system would allow people to steal six cents every now and then, but had means to prevent theft beyond that, I would feel safe with it as a merchant. I want to know if it is possible to s
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Re:Mirror (Score:5, Funny)
Another fun trick was to take a $1 and a $20 and cut them both in half. Then tape half of the $1 and the $20 to make two $21 dollar bills. Silly I know, but if you put them in a change machine, it would look for the numbers in the corners, it would read a 20 then a 1 and then give you $21 in change. You then took the other part and got $21 in change as well. Quick way to double your money. Now the machines check to make sure that all four numbers on the corners match up.
Re:Mirror (Score:5, Insightful)
Sounds like an urban myth to me. Would it add 20 and 20 from the corners of a normal $20 bill and give you $40 change?
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Maybe one rooted in truth, however. I can imagine a bill-reader using some simple image recognition against just one corner of the bill. You could get two $20 bills that way.
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That does remind me of when I managed a change machine at university. It would change 20p, 50p and £1 coins into 10p pieces. Some bright spark worked out (or heard) that you could wrap a 10p coin with tin foil and put it in the machine. Most times it would recognize the coin as 10 and just spit it out but one time in however many, it would take the coin and give change for 50p.
The fix? The machine had dip switches for what coins it would accept and there was one for 10p that was set to off. I set it t
Most entertaining... (Score:5, Informative)
is the line from the letter
"cease and desist the posting in any location of the material and information contained in this post"
Seeing as it is their SDK that contains the details of this "feature", are they going to send themselves a C&D and then pull the SDK?
Use microsoft == get screwed (Score:3, Insightful)
After about 30 years is this still news?
Use Microsoft software and you get screwed. They don't design software they design the user interface and botch the software. They are now as always a marketing not an IT company. It's always been that way, it will always be that way.
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In this case, it's Microsoft getting screwed by Microsoft. They are on the verge of paying, or have already paid, $2000 out-of-pocket to a guy who did a simple GET.
Entirely Microsoft's problem - except it'll become the guy's problem when he gets prosecuted for fraud. Faking a $100k transaction is not a smart move. The $1 transaction is a perfectly fine proof-of-concept.
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In this case, it's Microsoft getting screwed by Microsoft. They are on the verge of paying, or have already paid, $2000 out-of-pocket to a guy who did a simple GET.
They can't even validate user input where failing to do so directly costs them cash. They are not hiding behind some get out of everything license agreement and they still can't do the basics.
Re:Use microsoft == get screwed (Score:4, Informative)
Microsoft Research is not "people working for Microsoft", it's "people are paid by Microsoft not to work for Microsoft's competitors". Not a single meaningful Microsoft product or feature came from there.
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Not directly, anyway. Fair enough. But there are smart [msdn.com] people [msdn.com] at [msdn.com] microsoft [msdn.com] working directly on their retail products too.
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Microsoft Research is not "people working for Microsoft", it's "people are paid by Microsoft not to work for Microsoft's competitors". Not a single meaningful Microsoft product or feature came from there.
Huge chunks of .NET came out of MSR - generics, LINQ, etc. F# came out of MSR. If I remember correctly, Surface came out of MSR.
Truth is, a lot of stuff actually does come out of there, but it changes a fair bit when it's being "productized". It's certainly rare to get full products like that (F# is a notable exception), but specific features and ideas are often integrated into shipping products.
On the other hand, I'm not sure what you mean by "not working for competitors". Is Haskell a competitor to Micros
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A marketing company which subcontracts out its marketing and makes billions from software sales. That's a pretty weird marketing company.
Agreed they are pretty weird. They don't sell software though, they sell the dream of software that 'just works' to people that for the most part don't believe there is an alternative to bug ridden and low quality code.
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Source of URL (Score:4, Informative)
Solution (Score:3, Interesting)
All Microsoft needed to do was include a Message Authentication Code [wikipedia.org] (such as, say, HMAC-SHA1) in the tracking image URL. Microsoft and the merchant obviously already have a shared secret they can use for the purpose. Using a MAC would have been practically free.
Given what Microsoft pays its programmers, I'm just appalled that nobody thought to include basic precautions in a brand-new interface written in this day and age. Whoever wrote the Bing API specification really should have known better.
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Whoever wrote the Bing API was probably planning on exploiting it in exactly this fashion.
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A cleverer backdoor would have been a weak custom MAC (say, just the H(M) + secret). Then it'd still be exploitable, yet not obviously bad.
This article [root.org] goes into the reasons why HMACs are constructed the way they are, and about how naive constructions can be exploited.
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Sure. A MAC actually can mean two things, depending on context: an algorithm or a value. I'm going to use "MAC" to mean the algorithm, and "authenticator" to refer to the output of the algorithm. YMMV.
The MAC takes as input the message to be authenticated, M, and a key S. Let's say that M is information about the item to be purchased, and S is a password the merchant set up with Microsoft. Running the MAC on M and S produces A. The sender of the message sends both A and M to the re
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It's pretty clear that whoever designed this API didn't even take an passing glance at the security or reliability implications. There are 2 ways (from the linked slides) for a merchant to report cashback activity to MS:
1) Tracking pixel: this gives instant update to the user, but is completely insecure and also fairly unreliable (image fails to load, cross site https issues, random network hickup, etc).
2) FTP upload of a plain text list: yes really, plain old FTP. This is at least reliable but is only au
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Yep. You don't need SOAP per se, though. The important thing is having the merchant talk directly to Microsoft. Some people are oddly resistant to that notion though, and if you're going to use the tracking pixel approach, you need a MAC.
Agr
But then they put the key in plaintext in JS (Score:2)
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Merchants must at least have some ability to program, otherwise they wouldn't be able to create sites at all. Creating a MAC authenticator isn't hard: all you need to do is call a hash function a few times. But as another poster mentioned, the better thing to do is to just have the merchant talk directly to Microsoft and sidestep the whole problem.
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You're absolutely right. SHA-1 is sturdy enough, and would still have been a responsible choice[1]. Nevertheless, moving to one of the SHA-2 algorithms (like SHA-256 or SHA-512) moves the mental confidence gauge from "damn sure" to "would bet my career on it".
One point worth mentioning is that if you're worried about the output size of one of the SHA-2 hash functions (64 bytes is a little heavy), you can just truncate the output. SHA-512 truncated to the size of SHA-1 (160 bits) shouldn't be any less secure
mirrored post (Score:3, Informative)
http://lkcl.net/reports/bing.censorship.attempt [lkcl.net] - additional mirrors will be added as i find them.
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I simply screenshot it and uploaded it to an image host. *shrug* The cat is already out of the bag now, and MS will have to fix this.
Re: (Score:2)
fuck you. do not attempt to censor people's efforts to bring to your
attention your own stupidity. go fix the problem, and pay the guy who
found the problem a lot of money, as a thank you.
Microsoft's standard policy of thank-you for people who help them prevent multi-million losses is a free T-shirt.
You can't really hope for any better.
It's called fraud (Score:5, Insightful)
This is called "fraud". Look it up. It's been around for a long time, a lot longer than HTTP. There are standard business practices for dealing with it. Not all of them are technical. This system's technical defenses are probably sufficient to raise an alarm (delayed by a few weeks as the results are collated), and it will produce a pretty good paper trail leading to the owner of the Bing account. Some of the systems take into account minor details such as the existence of accountants, a police force, a paper trail, and a legal system. Obviously some stronger technical measures might have made it a bit more difficult to pull off this partucular fraud, or maybe it might have even stopped it, but the non-technical measures will also work just fine if they are called into play.
Whether or not the door is obviously guarded, it's still illegal to steal stuff from a store. The fact that the door was not protected with the latest and greatest in RFID theft detection systems doesn't change the fact that what you are doing is illegal. And perhaps the tracking process is slower than what you see in movies, people still get tracked down and arrested, days or weeks after the event. Moving from the streets onto the Internet doesn't really change the rules much (except that your case will probably wind up with Federal jurisdiction).
In this case, the poor "hacker" (I wish him/her luck!) appears to have done the following:
1. Used a specially formatted HTTP request to get a small fabricated purchase to show up as credited to his/her Bing account.
2. Noticed that the cash back did show up with no problem as "available for withdrawal".
3. Tried again with a much larger purchase. Again the purchase shows up in his account.
4. Hacker is hoping that the amount will soon become available for withdrawal.
On the other side of the world, the accounting systems for Microsoft and the associated merchant have likely compared invoices and noticed the discrepancies. The small ones got noted, but they were thrown out as "somebody is playing with the system, but it's not worth dealing with it". But this month, when going over the books, they're going to find a nice big 100,000 item that doesn't match up with any purchase recorded on the store's official records. However, they do have the account number of the buyer that should be getting the cash back. I'm not sure what typically happens at this point, but it probably involves cancelling dinner for the wolf pack so that by the time they're ready to send out the posse, the wolves are hungry.
In this case, Microsoft has apparently (I haven't looked into this) provided an API by which a store can report a sale and attribute the sale to a particular Bing account. The API has varying levels of security, depending on how much effort the store wants to put into preventing fake transactions from entering the system. Low effort might be fine and takes less time to set up, but it's easier to attack and that means more work to do when reconciling the accounts. Just like many other mechanisms for quickly distributing non-critical information between merchants, this isn't meant to be the authoritative information transmission system, just a way for people to keep status on accounts in between the regularly-scheduled account reconciliations. This way Bing can update your account balance within seconds of the purchase. Of course, the payback won't happen until they've gone back and checked Microsoft's records against the merchant's records and pulled out any differences. The differences go to the auditor and possibly to the police or FBI.
Could we maybe just think for a second before acting like jerks? Being a jerk means everybody suffers. I mean, just because I see a way to deface somebody's website doesn't mean I am obligated to do so. I walk by 100 cars a day, and I could easily spray shaving cream all over them and not get caught. But if everybody did that, quality of life would go down for everybody. Same thing on the internet.
I hate this attitude out there th
Re: (Score:2)
This way Bing can update your account balance within seconds of the purchase. Of course, the payback won't happen until they've gone back and checked Microsoft's records against the merchant's records and pulled out any differences. The differences go to the auditor and possibly to the police or FBI.
Only he's $0.06 was already avalible for withdrawl, i.e it had passed all the checks.
I hate this attitude out there that "if it isn't nailed down, I have every right to grab it and take it home, and if it is nailed down, I have every right to destroy it". I don't want a world (or even an Internet) where everything is nailed down and/or destroyed.
Actually i think the attitude is, if you are going to deploy software that deals with real money make it secure, the posting wasn't a "howto steal money from microsoft", it was just a blog post detailing a security flaw. There is a big difference between some blag with pictures of kittens and an online shopping system, implemented by a major IT company, If you can deface the homepage of a major IT company it shows incompete
Re:It's called fraud (Score:4, Interesting)
In this case, the poor "hacker" (I wish him/her luck!) appears to have done the following: 1. Used a specially formatted HTTP request to get a small fabricated purchase to show up as credited to his/her Bing account. 2. Noticed that the cash back did show up with no problem as "available for withdrawal". 3. Tried again with a much larger purchase. Again the purchase shows up in his account. 4. Hacker is hoping that the amount will soon become available for withdrawal.
5. Notified Microsoft about the issue?
Meanwhile, MS allowed a system where someone could redirect money to *someone else's* account, even an innocent third party. Imagine walking out of a local jewelry store, and the gate drops around you, sirens blare... all because a pickpocket put jewels in your pants. Imagine that instead of all of the sirens and gates, the store owner could have implemented a less expensive alternative that would have completely prevented the thief from doing this. So, the jewelry store is paying more to harass its customers... the store owners must enjoy it.
Re: (Score:2)
The cost of fraud is passed directly to the customer, it does not hurt Microsoft.
People keep repeating this claim, but the truth is, 90% of the time, cost is not proportional to price, it may eat into MegaCrops margins but they will not increase the price of a product in response if it looses them sales. Say you shoplift a TV from MegaCorp, they just lost $1000, that's bad, but if they pull away from the idea price point they may loose 10 sales, or if they drop the price 10% they will lose $1000 per 10 sales.
The concept scales everywhere, prices are not set at cost*1.n, they are set at
Hey Mercedes! (Score:3, Insightful)
Your car has an exploit, so I stole it and drove it into a wall to prove a point.
MS Response (Score:3, Funny)
Microsoft has posted this page in response:
http://www.bing.com/search?q=bing+cashback+vulnerability&go=&form=QBLH&filt=all&qs=n [bing.com]
Bing vulnerability? (Score:2)
What bing vulnerability?
Quote (Score:3, Insightful)
Regarding the tracking pixel approach: H.L. Mencken once wrote, "there is always a well-known solution to every human problem -- neat, plausible, and wrong." I cannot think of a situation to which this sentiment better applies.