New answers tagged

0

A lot of what I discussed in this answer about alternate SSH ports is applicable to this question. Since your goal is to be as invisible as possible*, I think your best bet is secure port knocking with a tool like fwknop (as noted in this crypto.SE question) or perhaps a custom one-time password scheme for sufficiently complicated port knocks (to help ...


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I've had this problem too. I don't believe OpenVPN alone changes the DNS without being told. If you're on Windows I recommend this, If you're using a Linux machine just change the DNS in "/etc/resolv.conf".


4

Yes, the VPN provider is able to see your data. If the data are not encrypted (i.e. HTTPS) the provider will be able to get to the clear text and will also be able to manipulate the data. The usual protections of HTTPS apply, i.e. the provider will see which site you visit but not the clear text data itself because they are encrypted. The provider will also ...


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In short, No! They see the IP of the VPN service and probably log it, and all your traffic including URL's IPs to your sites are encrypted. But if the VPN service is not encrypted, then the ISP could in theory can see all your traffic. However, if you are using a split tunneling mode, then the ISP can see your DNS queries and surfing traffic. Read more ...


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Which ISP do you mean? ISP connected directly to your computer? No, because your traffic is encapsulated. ISP of your VPN server? Yes, the ISP will know the destination IP address. In my opinion, try to use anonymity tools such as Tor or anonymous proxy.


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If your iphone is not jailbroken, and you did a factory reset (be sure of that) your datas are safe. For extra precaution you can also verify that all the possible accounts are deleted on the phone : google drive, dropbox, iCloud ...


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The use of redirection pages can be for multiple reasons. Issue a warning to the user that the pages is leading outside the original site network (legal requirements sometime) Counting the usage of outgoing links Filtering of addresses Data scrapping (this list is not exhaustive) The first could be seen as a security measure, which makes the user aware ...


0

The main benefit of separate keys is what happens in the worst-case scenario: someone gets your private key. SAME key on all hosts: The bad guys now have access to everything. DIFFERENT key on each host: The bad guys only have access to one thing. So--most secure? Unique keys for each host.


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This method should have following properties: Probability of false positives can be made as small as desired Server learns only the (approximate) number of items on each person's phone book, but not numbers themselves and cannot brute-force them Client-side brute-force attacks are impossible, as server can enforce policies against them Phones do not learn ...


1

With experience in the computer forensic field the short answer is Yes. As other people said it's called EXIF data. You can get information such as camera settings and lens used, time and date etc. On some newer camera models GPS tagging is available. Also all new smartphones have gps on them. Meaning when the photo is taken the GPS coordinates go in the ...


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It depends on what you are trying to achieve. If you are trying to prevent DNS leaks, DNSCrypt isn't what you need. DNSCrypt is intended to prevent DNS spoofing, which is quite different. You could think of it as Privacy vs Man-in-the-Middle. DNSCrypt is a protocol that authenticates communications between a DNS client and a DNS resolver. It prevents ...


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With Isemis mention of "probability of false positives" I thought about Zero-knowledge proof. This answer makes no claims to be secure as it was never reviewed, so others should review and comment it. I am no professional security expert either and I didn't have the time to make sure the low number of possible phone numbers might be a problem. User A and ...


0

Why hash them? Why not encrypt instead, and send them to your own server. That way neither client device has to have access to each other's contacts, and the server does most of the work. This does introduce a single point of failure though, the server. If it was compromised, the attackers could potentially access all numbers. This could be controlled if ...


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Modern Smart phones embed GPS coordinates into pictures. http://www.howtogeek.com/211427/how-to-see-exactly-where-a-photo-was-taken-and-keep-your-location-private/ This is often how sought out individuals are found and detained because they take photos with their phones unaware the photo contains the location as well. It all depends on the ...


1

Not officially, but there was a bug that was only recently fixed as documented on http://webkay.robinlinus.com/ that could gain access to currently logged in Google+ info. I think it's safe to assume there will be other vulnerabilities both present now or in future, just like there was another in the past that has also been fixed and don't forget there's ...


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How can we do this in a cryptographically secure way and respecting the users' privacy (i.e. without sharing the numbers in plain-text between them or with a server)? tldr: You can't. Hashing is great for certain uses, but this is probably not one of them. The reason is that an attacker would know that there are only 10 billion possibilities (for ...


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Let's do some tests! I started with a naive bash implementation, and calculated 10k numbers in 33 seconds: #!/bin/bash phone="2125551212" salt="abcdefghijklmnopqrstuvwxyz" shasalt() { echo "$* $phone $salt" | sha512sum; } for f in {1..10000} do shasalt $(shasalt $(shasalt)) >/dev/null # or write to a file... ((phone++)) done echo ...


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There are potentially other privacy issues you're not considering yet. By design your app makes it easy to see who is connected to a certain target. So an attacker creates one contact on their phone (the activist/informant/terrorist/victim they are interested in) and then connects to many other users through your app, to create a list of the target's ...


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Yes, it is (a bit) flawed. The problem is that the space is too small, so even with the multiple rounds and salts, it's relatively easy to bruteforce. Open Whisper Systems had a witty system where they provided an encrypted bloom filter that can be queried locally using blind signatures. They explain the process (as well as providing a good discussion of ...


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bcrypt would be a somewhat better approach because it is designed to be (programmably) slow. Using a large enough salt and a reasonable complexityFactor, bcrypt(salt + number, complexityFactor) should yield a viable hash and you avoid "rolling your own cryptography", which could possibly turn out to be a difficult sell. To increase security you just crank ...


1

Panopticlick is looking for things that make you different to other visitors. In this case, fewer people use canvas blockers than don't, so you become more unique if you use one. However, this only means that it is easier to tell you apart from another user - not that they can tell who you are. Think of it being like a security camera which can only see ...


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I have a hypothesis that it is an identifier (non-social security number) that companies will sell to each other to track everything you do. So far I have been asked by: Vanguard, Fidelity, Bank of America, eBay, Amazon, Netflix, Yahoo, Google, LinkedIn. I think there are more, but I forget. It may be centralized because they all ask in the same manner, with ...


2

I know that many giant companies has spent billions of dollars on how to prevent the privacy of their products but still they cant prevent it... So I am not expecting that I can get 100% solution on this, but still I want to protect it as much as I can. You've already got your answer, you just don't realize it. "As much as you can" is "not at all." ...


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Windows Embedded with the UI disabled would be a first step. Then you could: Disable the network Epoxy all open ports Remove the floppy drive (do these still exist) As all have said already, 100% is impossible, but if you look at each possible entry point and close it you can get close. Instead of the epoxy method you can setup a USB whitelist to ...


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As mentioned, its impossible to prevent capture of the displayed video - even in the worst case, the user can record the video on a smartphone or using a fixed camera (as some pirate movies do when they are recorded at the cinema) What you can do then is to shift the protection from stopping copying, to prosecuting copiers. You can embed watermarks in the ...


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Do not roll your own DRM scheme. The industry have tried and failed so many times that a homebrew solution will stand little chance. It would be better to "stand on the shoulders of giants" and use existing DRM solutions. Windows Media Rights Management and PlayReady are good solutions. The latter supports HDCP and are used by mainstream premium content ...


4

This is a problem of trying to protect what you want to provide. It's impossible to do, but you can make it difficult. Probably the best approach would be to encrypt the files. But at the end, you give all the data for a person to run on a computer they have full access to. Since it will play the video at some times, it means the keys will be available in ...


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As you state in the question, doing this in a foolproof way is technically impossible. For the video to be displayed on the screen it must somehow reside somewhere in the RAM on the computer, be transfered to the monitor and then displayed there. From all these points the video could be extracted. Possible ways include: Copied from RAM. Recorded with ...


0

If you are on a shared internet connection, you are behind a LAN. In this case, it appears to them as if you are all coming from one single computer. They should be unaware of who is torrenting. However, there are advanced methods by which it may be possible to tell, remotely, which computer is responsible. Computers' networking stack has a partially-unique ...


1

Consult Shaw's TOS and AUP http://www.shaw.ca/terms-of-use/ He probably got two notices, one being a DMCA copyrighted material download and the other being that excess upload traffic was being used. This is common on cable systems where the upload channel involves shared resources and abuse affects everyone on the system As to Who, Shaw doesn't really ...


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Very good question. Metadata is insanely powerful, and most people just don't realize how powerful it can be. Fortunately, it's not that hard to discover if you do a little digging into how technology and the internet works. I'm of the opinion that it's not very easy to hide online. In most cases, if you're a small fry, nobody's going to pay attention to ...


2

Have you read Google's TOS and PP? It says they will divulge any information they deem necessary to comply with any enforceable legal request. **We will share personal information with companies, organizations or individuals outside of Google if we have a good-faith belief that access, use, preservation or disclosure of the information is reasonably ...


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Using the same private key across separate domains is basically secure. If you authenticate to a system, you don't give away you private key, and that system cannot impersonate you. So you can use your key across work and personal systems, and a work system cannot then access your personal systems. However, there are often reasons to use different keys. For ...


0

I'm an expert on this particular issue and I can assure you that No, you do NOT need to worry about Skype compromising the security of your computer. Skype should be the LEAST of your worries. The most important thing to remember for the security of your computer is: Don't open any file attached to an email UNTIL you have verified who it came from, you know ...


0

It deppends, of course but, imagine you go shopping and, when paying, the most kind and honest employee ever made asks for your name, date of birth and some other personal info (not so harmfull at first sight). Would you answer the questions? Long story short is: it all deppends on your principles And, to be honest, nowadays people share 95% of their ...


2

First: privacy and the level of privacy someone wants to achieve is a very individual thing. Second: That said, it is difficult to explain to some people why they should care much, but what I found worked for me is following analogy: You lock the door to your appartment - totally independend of weither you have valuables in there or not. You also never ...



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