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3

The best over all solution is to use a commercial payment handling service that deals with all of that for you. For that transaction volume, the danger of having card data stored on prem out weighs your need for the data. If this is a retail business, I would suggest something like square, which would essentially put the responsible handling of data in ...


-2

The keys are generated without user input, keys should of course be random. The keys are simple strings of dictionary words, not very secure against anyone with the ability to access your unencrypted calls.


0

Usually you have a constant realm and in this case HA1=MD5(username:realm:password) could be stored instead of the password. But, if the password is only used for the SIP account, it actually does not matter if within a attack against the provider username and password get seized or HA1 instead, because the latter is all it needs to authenticate as the user. ...


1

Above is a packet capture of communication between my phone and Google's server(74.125.68.19). Apparently, TLS is used to protect data in transit. TLS is also used for your browser's connection to a HTTPS website so the security is comparable. If transmitted over cellular networks, there is a second layer of encryption between your phone and your ...


2

As long as you are working with only online needs for the password for integrating with a system while the user is logged in, then you should store the passwords encrypted with both a database key as well as a derived key based on the user's password for your service. When the user submits the password for their login, you can use that to produce a password ...


2

If you need to retrieve the plaintext password at some point, then you indeed need encryption and not hashing (beware that many people call "encryption" what really is hashing). I suppose that your "business need" comes from the need to support some protocol where the server must know the plaintext password (e.g. the APOP authentication method in the POP ...


3

No, most cryptographic methods that are considered secure are based around assuming every computer in the world is working on the problem non-stop and it still takes to the heat death of the universe. Sure it could be used to break less secure encryption, and in fact, using a super computer to crack such weak keys is effectively the same thing as using a ...


2

For "symmetric cryptographic algorithms" (symmetric encryption, MAC...), things are simple: a non-broken cryptographic algorithm is such that it uses an n-bit key, and the fastest method to find the key is trying out all possible keys until the right one is found (that is called exhaustive search or brute force). The algorithm is said "non-broken" precisely ...


3

Cookies are domain-dependent. You don't decide, from the server side, which cookie you read; the browser sends the stored cookies that match the name (with domain) of the target server. If you want to share some authentication in some SSO manner, then you need both servers A and B to delegate the authentication to a common third server C. That server will ...


0

Some wireless access points implement client separation to prevent comms between connected devices more detail here: Wireless client isolation - how does it work, and can it be bypassed? this would help to prevent the unencrypted traffic being viewed. But even with that in place if the encryption is based on a pre-shared key (PSK) and the attacker has the ...


3

The general answer is: do some reverse-engineering on the application. This notion of "reverse-engineering" is rather large; it includes: Reading the documentation (if any) or other design notes accompanying the application. Talking with the developers who built that application (it is amazing what people will say after two or three pints). Going through ...


0

Edit: Reading this post: Are WPA2 connections with a shared key secure? I realise that I know too little about the topic. Original post remains below. Does Wifi encryption create a private tunnel between the adapter and the accesspoint? No. Not even with 802.1X Authentication. -> See https://en.wikipedia.org/wiki/IEEE_802.1X#Shared_media When non ...


-1

Tools to see it: PEiD with the Krypto Analyzer (KANAL) plugin Keygener Assistant IDA Pro with the Findcrypt OllyDbg with the SnD Crypto x3chun's Crypto Searcher Hash & Crypto Detector (HCD) Draft Crypto Analyzer (DRACA) To know how to run linux tools learn bfcrypt - Crypto scanner


1

In spite of being possible to read/write data to SSL/TLS channels as with vanilla TCP/IP sockets, in Java or C or whatever, SSL provides you the concept of SSL session, which can be kept across several TCP/IP connections. Thus, IMHO this makes SSL a session layer protocol (I wonder why someone came up with the TLS name...).


4

Unless "website A" and "website B" are both subdomains of the same domain, what you want to do is impossible; if they are subdomains of the same domain, the same person or organization presumably controls both. Consequently, legality is irrelevant.


-1

No, the privacy of clear text data does not depend on the encryption mode of the network, assuming that other (legitimate) machines are connected to the same access point. By default machines will not show (clear text data) traffic of other machines, however it is possible to do so using tools that poison the ARP table, this is called (you guessed it right) ...


2

First, a comment; sometimes (read "almost always") I get a cool new toy, app, technology and I try to fit it in in every possible place. Even in places that don't work, I enjoy figuring out why. It's a learning experience. The term "Threat Model" may sound either overly theoretical, or dismissive of your case. The purpose is for the security consultant ...


1

Having once worked at an edu, it was our goal to make things as seamless and painless for the clients (students) of the University. As a professional, there were many things that we championed for especially when it came to security. For example, we opposed P2P network, because traffic patterns at the time pointed to students downloading music (back then ...


0

The actual format of NaCL's output is not completely specified -- or, rather, it is specified as being the raw output from some cryptographic primitives (as described there). The format is thus non-extensible and does not include any feature supporting multiple recipients. Ability to send a message to multiple recipient appears to be a functionality that has ...


4

You can have SSL/TLS without certificates. This is supported in the TLS standard: the "DH_anon" cipher suites involve no certificate whatsoever. But you have to remember that such an unauthenticated TLS is inherently weak against active attackers, since they cannot prevent client or server impersonation (or both at the same time, which is called a ...


1

Seems to me the number was converted into hexadecimal, and then put through base64. This is only coding, no key was used, it is not encryption. To reverse it, you can do echo "73L0zaw06WGCxKQIKkiQnlvav8XyVUyeVT3qU6uWLXXbpG71J5Q8TzArk/DBR+Vw" | base64 -d | xxd to see the value in hexadecimal. Then use Python for instance to convert the hex number found into ...


0

Regarding alternatives to certificate based (asymmetric) encryption for communication protocols, symmetric encryption is a possibility such as a shared key known by both parties. Considering alternatives to SSL and in particular certificates, consider encrypting the data before it is placed on the wire. This would allow you to use any number of protocols ...


4

SSL/TLS (the underlying protocol for HTTPS) provides two features: Encryption, so that nobody could passively listen to the data. Encryption is done using a key which is somehow shared between the peers. Identification, so that you can be sure who you are talking to. This is usually done with certificates. While you might have encryption without ...


0

The data over https connection is encrypted using a private key, which is known to both sender and receiver. The sender encrypts the data using the private key and the receiver uses the same key to decrypt the data. The same key is not reused again to prevent the replay attacks. Therefore, a unique key must be used in every session. Now, the question is ...


0

No, you can't have HTTPS without use of SSL Certificate/public key. With SSL Certificate the server identifies itself to client. If you having Self-Signed Certificate you'll have HTTPS, but self-signed certificate is not trusted by modern browsers.


0

As the traffic leaves the university it sets on a long long journey across the globe until it reaches the server it was meant for. During that it passes lots of countries and uses lots of people's datacenters. They all can spy on you. You need strong end-to-end (TLS) protection to be safe from those people. With encrypted WiFi you can protect from others ...


4

I think you are worrying about the wrong thing. You should have no reason to trust the local network any more than you would for any data you'd send over the public internet. If you want to send a password, it's your responsibility to ensure you're using a connection protected by TLS. Trusting the local WiFi to protect your data is essentially excluding ...


0

Without the JCE Unlimited Strength Policy files in place, Java is able to use "strong but limited cryptography". That isn't limited to 128-bit or less necessarily. Just that "the jurisdiction policy files distributed with the Java SE 7 software have built-in restrictions on available cryptographic strength." From the README.txt: Due to import control ...


1

There's two things encryption does: it makes interception of communications harder. Text sent in the clear is trivially easy to 'pick up' by anyone on the communication path you're using. If you 'have nothing to hide' then this may seem irrelevant, but bear in mind that there are plenty of unscrupulous types out there who are prepared to use personal ...


0

Update as of Nov. 19, 2014 A security analysis of BTSync from a group at Hackito 2014 has been released, with generally unfavorable results. An official response from BitTorrent seems to address many of the issues raised. BitTorrentsync security & privacy analysis – Hackito Session results* *Discussion on HN BitTorrent official response to Hackito ...


3

This was just a comment... tl;dresearch: as far as I know the only threat in your scenario would *potentially* come from a cold boot attack if the attacker could freeze your phone and do nasty things to it. Full disk encryption stores the decrypted file to be accessed in volatile memory. Thus, if the power is disrupted by any means, disk is left encrypted ...


1

The equivalent data for ECDSA, or any ECC including ECDH, is the public point value and a specification of the curve used. In practice for interoperability people use one of the curves identified by a standardized OID (NIST, SECG, etc) and mostly only the two "blessed" by NSA Suite B, namely nistp256 and nistp384, although the ASN.1 formats (and openssl ...


3

From what I can tell from the comments, you want to use stronger and weaker passwords depending on the sensitivity of the file. For that, I suggest a different approach: Instead of having different passwords, require an extra password for the more sensitive documents. So all files are encrypted by default by the standard password, and the more sensitive ...


3

From Wikipedia: A 2013 attack by Xie Tao, Fanbao Liu, and Dengguo Feng breaks MD5 collision resistance in 2^18 time. This attack runs in less than a second on a regular computer.[2] This means that there's a weakness in MD5's ability to distinguish between different input data - that two arbitrary inputs may calculate the same hash. In April 2009, ...


0

Unfortunately I think it's highly unlikely that you'll be able to recover any of the original encrypted data. Even if the data wasn't encrypted, the new installation of Windows would have overwritten many of the original files. The encryption that was originally there makes it nearly impossible. Commercial data recovery software works by scanning empty ...


4

Why it does not guarantee integrity is easier to see in the case of a stream cipher like RC4, where the encryption is a bit-by-bit XOR of the data with a key-dependent stream. Basically, the encryption of message m is: e = m XOR sk, where sk is the RC4 output (a long stream of pseudorandom bits produced from the key k). Suppose that you ...


2

The problem is that hashing provides nothing in terms of integrity in your scenario. You are relying on the encryption alone to assert integrity. If I get a hold of the message and decrypt it, I could alter the message, recalculate the hash, encrypt it again and pass it on. If you trust encryption alone to provide integrity, then this process works, but ...


0

Some companies refuse to permit PGP or s/MIME encrypted emails into their environment, because encrypted attachments can't be scanned for viruses/spam, etc. This is a part of defense in depth, and usually includes MTA scanning (MSFT hosted forefront, Symantec, Proofpoint, etc) Server scanning (Trend Micro for Exchange, ?? for Lotus Notes...) Desktop ...


1

Yes, if you receive, transmit, or store cardholder data in any form, you are required to comply with PCI-DSS. In fact, one of the things that you're required to do under PCI-DSS is encrypt that data using strong encryption. Though I am not a PCI auditor, I would suspect that RC2 would not, if fact, be considered strong encryption, so not only are you ...


0

Risky Behavior A survey of businesses in the U.S. and Europe reveals activities that may put cardholder data at risk. 81% store payment card numbers 73% store payment card expiration dates 71% store payment card verification codes 57% store customer data from the payment card magnetic stripe 16% store other personal data Source: Forrester Consulting: ...


0

Encrypted emails are also plain text. This might sound like a paradox, but its not. When you encrypt a email message, the email body is replaced by the encrypted ASCII-armoured text, which is a simple BASE64-representation of the original encrypted data. Attachments are also plain text, all attachments are converted to BASE64 Before put in the email message. ...


1

If the underlying algo's and methods (i.e. including signing) are the same then the reliance on the actual encryption is no different and in the real-world there is little difference in risk. From a theoretical cryptanalysis standpoint one could argue that if the plaintext covering email provided context it would aid an attack on the cipher text, but modern ...


-1

Use the LUKS Nuke method, it will destroy the LUKS header - which includes the key used for decryption - upon entering a specific password. Once the adversary enters this Nuke Password, the LUKS header will be destroyed and it will be impossible to decrypt the drive even if the real decryption password is beaten out of you, since the header is not existent ...


0

All the details of proper database information handling go well beyond the scope of a quick StackExchange answer. You really want to do this the right way. Part of your problem is the architecture where the database, and the web app accessing the sensitive info are on the same server. If that server gets compromised, so does the keying material for any ...


4

In computing, Real-Time means the study of systems that must operate within strict time constraints. This is a very large class of systems, and it tends to include most applications with a user interface. For instance, if you go to Youtube and view a video, then this is a real-time application: the downloading, decompression and display of the pictures must ...


4

Fiddler captures HTTPS traffic by generating on-the-fly a fake certificate for the intended server, thereby running a complete Man-in-the-Middle attack. This requires that the client is configured to accept the Fiddler-controlled CA as a trusted CA, as described in the documentation. This kind of interception breaks client certificates. When there is a ...


11

To complement the answer from @raz, one must be aware of Protocol Downgrade Attacks. Browsers like IE send their maximum supported version, and then the server chooses (in your case, IE says "I know up to TLS 1.2" and the server responds with "we will do TLS 1.0"). However, browsers know that there exist buggy servers out there, that will simply have an ...


9

The server chooses which cipher suite to use for establishing the secure channel. The client (browser) poses the protocols and encryption algorithms that it will accept. The server chooses the one it deems most secure (based on its own list of acceptable protocols) and that is used for the secure channel. If the server does not see any cipher suites that ...


0

Keep in mind the key to measuring security is not just entropy of the password, but the weakest link in the chain. In this case, physical security of the computer plays a part in addition to if the machine is on a windows domain. It is fairly trivial to reset any windows password using Trinity provided that you can mount a DVD in the drive and reboot the ...


1

Wireless protocols, or even wired protocols, are based on packets, often called frames. A typical frame will have a checksum, that is used to detect whether the frame was damaged or not. If the frame is detected as damaged, it is dropped altogether; it is up to the upper layers to provision for acknowledge and reemission of missing frames (that's what TCP ...



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