What's new arround internet
| Src | Date (GMT) | Titre | Description | Tags | Stories | Notes |
 |
2020-01-28 14:24:42 | How to decrypt WhatsApp end-to-end media files (lien direct) | At the center of the "Saudis hacked Bezos" story is a mysterious video file investigators couldn't decrypt, sent by Saudi Crown Prince MBS to Bezos via WhatsApp. In this blog post, I show how to decrypt it. Once decrypted, we'll either have a smoking gun proving the Saudi's guilt, or exoneration showing that nothing in the report implicated the Saudis. I show how everyone can replicate this on their own iPhones.The steps are simple:backup the phone to your computer (macOS or Windows), using one of many freely available tools, such as Apple's own iTunes appextract the database containing WhatsApp messages from that backup, using one of many freely available tools, or just hunt for the specific file yourselfgrab the .enc file and decryption key from that database, using one of many freely available SQL toolsdecrypt the video, using a tool I just created on GitHubEnd-to-end encrypted downloaderThe FTI report says that within hours of receiving a suspicious video that Bezos's iPhone began behaving strangely. The report says:...analysis revealed that the suspect video had been delivered via an encrypted downloader host on WhatsApp's media server. Due to WhatsApp's end-to-end encryption, the contents of the downloader cannot be practically determined. The phrase "encrypted downloader" is not a technical term but something the investigators invented. It sounds like a term we use in malware/viruses, where a first stage downloads later stages using encryption. But that's not what happened here.Instead, the file in question is simply the video itself, encrypted, with a few extra bytes due to encryption overhead (10 bytes of checksum at the start, up to 15 bytes of padding at the end).Now let's talk about "end-to-end encryption". This only means that those in middle can't decrypt the file, not even WhatsApp's servers. But those on the ends can -- and that's what we have here, one of the ends. Bezos can upgrade his old iPhone X to a new iPhone XS by backing up the old phone and restoring onto the new phone and still decrypt the video. That means the decryption key is somewhere in the backup.Specifically, the decryption key is in the file named 7c7fba66680ef796b916b067077cc246adacf01d in the backup, in the table named ZWAMDIAITEM, as the first protobuf field in the field named ZMEDIAKEY. These details are explained below.WhatsApp end-to-end encryption of videoLet's discuss how videos are transmitted using text messages.We'll start with SMS, the old messaging system built into the phone system that predates modern apps. It can only send short text messages of a few hundred bytes at a time. These messages are too small to hold a complete video many megabytes in size. They are sent through the phone system itself, not via the Internet.When you send a video via SMS what happens is that the video is uploaded to the phone company's servers via HTTP. Then, a text message is sent with a URL link to the video. When the recipient gets the message, their phone downloads the video from the URL. The text messages going through the phone system just contain the URL, an Internet connection is used to transfer the video.This happens transparently to the user. The user just sees the video and not the URL. They'll only notice a difference when using ancient 2G mobile phones that can get the SMS messages but which can't actually connect to the Internet.A similar thing happens with WhatsApp, only with encryption added.The sender first encryp | Malware Hack Tool | ||
|
2019-05-27 19:59:38 | A lesson in journalism vs. cybersecurity (lien direct) | A recent NYTimes article blaming the NSA for a ransomware attack on Baltimore is typical bad journalism. It's an op-ed masquerading as a news article. It cites many to support the conclusion the NSA is to be blamed, but only a single quote, from the NSA director, from the opposing side. Yet many experts oppose this conclusion, such as @dave_maynor, @beauwoods, @daveaitel, @riskybusiness, @shpantzer, @todb, @hrbrmst, ... It's not as if these people are hard to find, it's that the story's authors didn't look.The main reason experts disagree is that the NSA's Eternalblue isn't actually responsible for most ransomware infections. It's almost never used to start the initial infection -- that's almost always phishing or website vulns. Once inside, it's almost never used to spread laterally -- that's almost always done with windows networking and stolen credentials. Yes, ransomware increasingly includes Eternalblue as part of their arsenal of attacks, but this doesn't mean Eternalblue is responsible for ransomware.The NYTimes story takes extraordinary effort to jump around this fact, deliberately misleading the reader to conflate one with the other. A good example is this paragraph: That link is a warning from last July about the "Emotet" ransomware and makes no mention of EternalBlue. Instead, the story is citing anonymous researchers claiming that EthernalBlue has been added to Emotet since after that DHS warning.Who are these anonymous researchers? The NYTimes article doesn't say. This is bad journalism. The principles of journalism are that you are supposed to attribute where you got such information, so that the reader can verify for themselves whether the information is true or false, or at least, credible.And in this case, it's probably false. The likely source for that claim is this article from Malwarebytes about Emotet. They have since retracted this claim, as the latest version of their article points out. In any event, the NYTimes article claims that Emotet is now "relying" on the NSA's EternalBlue to spread. That's not the same thing as "using", not even close. Yes, lots of ransomware has been updated to also use Eternalblue to spread. However, what ransomware is relying upon is still the Wind |
Ransomware Malware Patching Guideline | NotPetya Wannacry | |
|
2019-04-21 17:16:36 | Was it a Chinese spy or confused tourist? (lien direct) | Politico has an article from a former spy analyzing whether the "spy" they caught at Mar-a-lago (Trump's Florida vacation spot) was actually a "spy". I thought I'd add to it from a technical perspective about her malware, USB drives, phones, cash, and so on.The part that has gotten the most press is that she had a USB drive with evil malware. We've belittled the Secret Service agents who infected themselves, and we've used this as the most important reason to suspect she was a spy.But it's nonsense.It could be something significant, but we can't know that based on the details that have been reported. What the Secret Service reported was that it "started installing software". That's a symptom of a USB device installing drivers, not malware. Common USB devices, such as WiFi adapters, Bluetooth adapters, microSD readers, and 2FA keys look identical to flash drives, and when inserted into a computer, cause Windows to install drivers.Visual "installing files" is not a symptom of malware. When malware does its job right, there are no symptoms. It installs invisibly in the background. Thats the entire point of malware, that you don't know it's there. It's not to say there would be no visible evidence. A popular way of hacking desktops with USB drives is by emulating a keyboard/mouse that quickly types commands, which will cause some visual artifacts on the screen. It's just that "installing files" does not lend itself to malware as being the most likely explanation.That it was "malware" instead of something normal is just the standard trope that anything unexplained is proof of hackers/viruses. We have no evidence it was actually malware, and the evidence we do have suggests something other than malware.Lots of travelers carry wads of cash. I carry ten $100 bills with me, hidden in my luggage, for emergencies. I've been caught before when the credit card company fraud detection triggers in a foreign country leaving me with nothing. It's very distressing, hence cash.The Politico story mentioned the "spy" also has a U.S. bank account, and thus cash wasn't needed. Well, I carry that cash, too, for domestic travel. It's just not for international travel. In any case, the U.S. may have been just one stop on a multi-country itinerary. I've taken several "round the world" trips where I've just flown one direction, such as east, before getting back home. $8k is in the range of cash that such travelers carry.The same is true of phones and SIMs. Different countries have different frequencies and technologies. In the past, I've traveled with as many as three phones (US, Japan, Europe). It's gotten better with modern 4G phones, where my iPhone Xs should work everywhere. (Though it's likely going to diverge again with 5G, as the U.S. goes on a different path from the rest of the world.)The same is true with SIMs. In the past, you pretty much needed a different SIM for each country. Arrival in the airport meant going to the kiosk to get a SIM for $10. At the end of a long itinerary, I'd arrive home with several SIMs. These days, however, with so many "MVNOs", such as Google Fi, this is radically less necessary. However, the fact that the latest high-end phones all support dual-SIMs proves it's still an issue.Thus, the evidence so far is that of a normal traveler. If these SIMs/phones are indeed because of spying, we would need additional evidence. A quick analysis of the accounts associated with the SIMs and the of the contents of the phones should tells us if she's a traveler or spy.Normal travelers may be concerned about hidden cameras. There's this story from about Korean hotels filming guests, and this other one about | Malware | ||
|
2018-06-27 15:49:15 | Lessons from nPetya one year later (lien direct) | This is the one year anniversary of NotPetya. It was probably the most expensive single hacker attack in history (so far), with FedEx estimating it cost them $300 million. Shipping giant Maersk and drug giant Merck suffered losses on a similar scale. Many are discussing lessons we should learn from this, but they are the wrong lessons.An example is this quote in a recent article:"One year on from NotPetya, it seems lessons still haven't been learned. A lack of regular patching of outdated systems because of the issues of downtime and disruption to organisations was the path through which both NotPetya and WannaCry spread, and this fundamental problem remains." This is an attractive claim. It describes the problem in terms of people being "weak" and that the solution is to be "strong". If only organizations where strong enough, willing to deal with downtime and disruption, then problems like this wouldn't happen.But this is wrong, at least in the case of NotPetya.NotPetya's spread was initiated through the Ukraining company MeDoc, which provided tax accounting software. It had an auto-update process for keeping its software up-to-date. This was subverted in order to deliver the initial NotPetya infection. Patching had nothing to do with this. Other common security controls like firewalls were also bypassed.Auto-updates and cloud-management of software and IoT devices is becoming the norm. This creates a danger for such "supply chain" attacks, where the supplier of the product gets compromised, spreading an infection to all their customers. The lesson organizations need to learn about this is how such infections can be contained. One way is to firewall such products away from the core network. Another solution is port-isolation/microsegmentation, that limits the spread after an initial infection.Once NotPetya got into an organization, it spread laterally. The chief way it did this was through Mimikatz/PsExec, reusing Windows credentials. It stole whatever login information it could get from the infected machine and used it to try to log on to other Windows machines. If it got lucky getting domain administrator credentials, it then spread to the entire Windows domain. This was the primary method of spreading, not the unpatched ETERNALBLUE vulnerability. This is why it was so devastating to companies like Maersk: it wasn't a matter of a few unpatched systems getting infected, it was a matter of losing entire domains, including the backup systems.Such spreading through Windows credentials continues to plague organizations. A good example is the recent ransomware infection of the City of Atlanta that spread much the same way. The limits of the worm were the limits of domain trust relationships. For example, it didn't infect the city airport because that Windows domain is separate from the city's domains.This is the most pressing lesson organizations need to learn, the one they are ignoring. They need to do more to prevent desktops from infecting each other, such as through port-isolation/microsegmentation. They need to control the spread of administrative credentials within the organization. A lot of organizations put the same local admin account on every workstation which makes the spread of NotPetya style worms trivial. They need to reevaluate trust relationships between domains, so that the admin of one can't infect the others.These solutions are difficult, which is why news articles don't mention them. You don't have to know anything about security to proclaim "the problem is lack of patches". It's moral authority, chastising the weak, rather than a proscription of what to do. Solving supply chain hacks and Windows credential sharing, though, is hard. I don't know any universal solution to this -- I'd have to thoroughly analyze your network and business in order to | Ransomware Malware Patching | FedEx NotPetya Wannacry |
1
We have: 4 articles.
We have: 4 articles.
To see everything:
Our RSS (filtrered)
