Tagged Questions

A description and set of rules for the ordered exchange of structured information designed with the goal of protecting the security of the system.

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2
votes
1answer
39 views

Masking traffic in another protocol

I remember reading a couple of years ago (I believe it was during the Egyptian Revolution) that hackers managed to bypass government filters by making their traffic appear as another protocol. If ...
2
votes
2answers
595 views

Can Poodle be fixed in SSLv3 or will it go the way of TLS compression?

Is TLS_FALLBACK_SCSV going to be the fix for servers that wish to keep SSLv3 enabled? If not what actions are being taken, if any, that address the vulnerability besides disabling SSLv3?
3
votes
0answers
67 views

Is it possible to retrieve SSH v2 credentials in a username/password authentication scheme?

I'm currently analysing a compromised network(root access has been gained to a workstation and logs show that it has been used for port scanning and service brute forcing attacks on the remaining ...
0
votes
2answers
63 views

Impossible to make connections through closed ports?

If you have closed all your ports on your internet protocol, you cannot make a connection to that internet protocol. So how do attackers (DoS or any other means that need a connection) make a ...
8
votes
1answer
977 views

Why would HTTP client only send authentication headers once an unauthenticated request was rejected?

The default usage of HttpClient and HttpWebRequest .NET classes is setting Credentials property and then asking the class instance to perform an HTTP request. If the target requres Basic authorization ...
1
vote
1answer
87 views

What network protocol is Crashplan using?

I have been using CrashPlan for a while internally (i.e. local backup server). I would also like to setup off-site backup but my experience is that I have to forward a port from the router sitting at ...
0
votes
0answers
46 views

Payment Application Integration - Encryption or HMAC

Doing an integration with an online payment provider. Payment provider will be making a web request to my server to provide some information about the basket content. On my end there's no payment ...
0
votes
1answer
49 views

Basis Authentication Protocol: a concrete attack

Below is an informal protocol narration of a simple authentication protocol. A sends to B a signed hash of message M, B's name and a nonce N. B knows that the message M is intended for him, that it ...
0
votes
1answer
103 views

A no-login approach to authenticating a certain device, MAC-Address as password?

I have created a REST api, and now i'm thinking about authentication. I want the mobile application's flow for the user to be very simple: only having to enter a username and then this username ...
0
votes
2answers
82 views

What are the alternatives to ECDSA for an authentication protocol?

In an authentication protocol, S has a public/private key pair known to C, and S and C have established a secure channel (for example, using DH or ECDH, or any other key exchange protocol). C wishes ...
1
vote
2answers
55 views

Is it possible to implement a secure game without having a reliable arbiter?

N players are playing a perfect information game (the kind of game where everyone knows moves of everyone) by making moves by turn (P1, P2, ..., Pn, P1, ..., Pn, ... till the game will finish). Game ...
2
votes
2answers
245 views

How does the SSL connection protocol work with self-signed certificate?

I'm using the self-signed certificate, but I don't know how this protocol works. I connect two apps with a socket SSL and it works fine. The server is a Python app and the client is an Android app. I ...
3
votes
4answers
259 views

What's the need of multiple implementations of SSL/TLS? [closed]

I've been reading about SSL/TLS and I was surprised when I saw the amount SSL/TLS implementations that exist. wikipedia. So, is there really a need for all these different implementations? Wouldn't ...
-1
votes
1answer
1k views

Why is the deprecated SSL 2.0 protocol considered insecure and how can it be exploited?

I am making a presentation to the class about "SSL 2.0 deprecated protocol" and I really have no idea how this exploit is used or how the attacker can use this vul. I understand the impact of this ...
1
vote
2answers
67 views

What cryptographic protocol is appropriate for the case where user needs access to a binary and encrypted configuration files?

This is a very newbie IT security question... I have to quickly implement a solution for our application that works like this... We have a binary executable that is given a configuration file. I need ...
3
votes
1answer
168 views

How to fix this broken crypto protocol?

I am considering a protocol where you upload a one time pad to a server, using public key encryption and then the result (using the pad) is sent back in plaintext: Alice uses Bobs RSA public key to ...
1
vote
1answer
454 views

What is the different between CMP and SCEP protocol?

What is the different between CMPV and SCEP protocol? Which one is better ?
1
vote
1answer
69 views

Any known protocol for establishing trust between an inherently untrustworthy source and a server without a 3rd party?

Is there any kind of protocol, scheme, or theoretical paper out there that implements or examines the problem of establishing trust between two parties (communicating, listening) where the ...
2
votes
4answers
650 views

Are custom protocols insecure?

So, I know rolling your own security is ill-advised, but for simplistic things like communicating with a home server, say, updating a grocery list, is a custom protocol fine? It won't be doing ...
0
votes
2answers
364 views

What TLS and SSL protocols should I have turned on

I am using Explorer as my browser. What do I have to have on regarding the TLS and SSL protocols. There are several of each one.
1
vote
2answers
58 views

What steps remain for a robust, neutral and surveillance-proof Internet? [closed]

Recent leaks about widespread NSA surveillance have brought privacy and security to the forefront of the public consciousness as we strive to determine best practices in governance for the Internet ...
6
votes
1answer
1k views

What does chacha20-poly1305@openssh.com mean for me?

OpenSSH just introduced a new protocol, chacha20-poly1305@openssh.com, which combines the two algorithms from DJB: ChaCha20 and Poly1305-AES. It was inspired by a similar proposal for TLS, which ...
0
votes
1answer
124 views

How to extract the top-level of protocols into the csv file by using tshark command?

Here is what I tried: tshark -r test.pcap -T fields -e ip.proto > output.csv But this can only show all the protocols in the csv files. I want to show only the top level of protocol numbers such as ...
1
vote
1answer
54 views

Protocols that are highly resistant to code injection attacks ? [closed]

After reading about language based security, it seems protocols that are defined using context-free or regular grammars are highly resistant to code injection attacks. Are there any good security ...
2
votes
0answers
85 views

Main difference between Yahalom and Needham-Schroeder key exchange protocols

I am just wondering what is the main difference between the Yahalom and Needham-Schroeder key exchange protocols? Which protocol uses less computational power?
1
vote
1answer
84 views

The need for created timestamp in tokens

In different token, for example SAML, I have encountered I have seen that it includes the timestamp for when it was created. I understand the reason for a expiration timestamp, but before the token is ...
2
votes
1answer
287 views

Using Diffie–Hellman key protocol to create a safe secret key

Let's say, I have a friend far from me and I want to send some secret messages to him. I have to say, I'm pretty newbie in security. That's why I'm wondering, does the Diffie–Hellman key exchange ...
1
vote
1answer
93 views

Two way delegation?

I am looking into using the X.509 for mutual delegation where mutual delegation is bi-directional where an entity can only delegate a task or a set of permissions to another entity if the latter is ...
4
votes
3answers
2k views

Safe to expose Active Directory via LDAPS externally?

We currently access Active Directory via LDAPS internally for authentication and user data retrieval. Is it common, or safe, to expose this publicly over LDAPs? Addendum 1: Our business case, ...
-1
votes
3answers
522 views

China CCTV System UDP protocol isn't working

My boss is trying to invest on a CCTV solution that he orders from China, his idea is to market it here after we fine tune the process and configuration and make a few tweaks of our own. It consists ...
5
votes
1answer
2k views

What block ciphers and algorithms are now safe? [closed]

I work for a large non-US based international organisation. Regarding the recent leaks about the NSA breaking most encryption on the internet, we now know the US and UK governments are actively ...
10
votes
2answers
408 views

How do new security and cryptography techniques/protocols avoid the chicken-and-egg problem?

. . .better solutions have been proposed and will be worth considering once they have withstood the test of time (i.e. “5 to 10 years in the field, and not broken yet”). -From Thomas Pornin's ...
1
vote
1answer
190 views

xmpp ssl cipher negotiation

Does anyone know how ssl ciphers are nogitiated via the xmpp protocol. When I capture packets, I see: <starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'/> There is no hello server/client or ...
1
vote
1answer
440 views

Wireshark detecting suspicious messages through jabber protocol, It says it is from my website, no idea what it is

I was doing a network scan on my computer with Wireshark and came up with something very suspicious: I found a stream with the jabber protocol. I do not have a jabber server set up nor do I have any ...
1
vote
2answers
1k views

Sending Syslog/SNMP information over the internet using standard UDP port 514

I'm looking into monitoring a Windows VPS by sending Syslog messages to a Synology NAS, which can generate email alerts and such. I also would like to use SNMP to generate health stats, and see trends ...
0
votes
1answer
178 views

Is it safe not to encrypt ping packets them?

I am running encrypted communication with ping tacked on after decryption and deserialization is complete. I.e. incoming data -> split into packets -> decrypt -> deserializer -> actual message or ...
3
votes
2answers
964 views

What risks are there with a Bluetooth based door lock, and are there any mitigations?

There are a few interesting Bluetooth door locks on the market that use version Bluetooth 4.0 however there seems to be a few issues with this E0 Encryption flaws Risks during pairing Attacks ...
10
votes
3answers
765 views

Is off-the-record style encryption possible with email?

The instant messaging world has off-the-record encryption - which means you get authentication, encryption, and forward deniability. Key material is published after a session ends such that an ...
3
votes
3answers
3k views

Disabling SSL v2 and weak ciphers on client PC's

Is it a requirement to also disable SSL v2 and weak ciphers on client PC's? I have seen quite a few posts for disabling them on servers, but nothing about a regular client PC, say, running Windows XP ...
2
votes
3answers
2k views

Uploading files through an HTTPS web application

We have a client facing web site. A certificate is required to land on the login page, where upon you then need a username and a password to further login. System has Apache servers acting as load ...
2
votes
0answers
84 views

In U-Prove, what is the purpose of “Pseudonyms”, “Committed”, and “Scope” values and how are they used?

U-Prove allows for anonymous authentication and authorization without the involvement of an IdP. When a client generates a presentation proof 3 values can be optionally included, but I can't find ...
1
vote
1answer
144 views

Is there a known vetted alternative to this key-exchange protocol?

I have three participants: A client A in possession of the public key Kpub A login server S in possession of the private key Kpriv Game servers B (B1, B2 etc) S and all B may share a finite number ...
2
votes
1answer
232 views

Any obvious flaws in this protocol?

Are there any particular flaws in this protocol? (Yes I know about SSL) Three participants: Login Server LS Game Server GS Client C Asymmetric key-pair Kpriv Kpub Shared 128bit secret key Ksec ...
-2
votes
2answers
143 views

Understanding a key establishment protocol

I'm studying a one-pass key establishment protocol. Let be A client and B the Server. A sends to B: E_w(t,b,k) where t is a timestamp requested for freshness, k is the ephemeral key that will be ...
3
votes
1answer
224 views

Secure information exchange between web applications using browser redirection

We're implementing a web application (US) that needs to exchange sensitive information with a third-party web application (THEM). The way we'd like it to work is that an end user clicks a hyperlink, ...
-3
votes
2answers
147 views

Problem with Encryption Protocol

I have a question about a encryption protocol, if it is good or not. Bob and Alice communicate over an insecure channel( a possible attacker can listen). An expert suggests the following protocol to ...
5
votes
5answers
3k views

How secure is using CRAM-MD5 for email authentication, when not using an SSL connection?

Background: My current server-provider tells me it's no problem to store the passwords in plain-text in the database, saying he has to do so because they use CRAM-MD5 for email authentication. My ...
0
votes
1answer
335 views

What is a man in the middle attack?

My university provided me with the following slide which is confusing me: From my understanding, what is happening here is that Trudy (Person in the middle) is pretending to be Alice. Bob then ...
1
vote
1answer
1k views

Symmetric Key Cryptography vs Public Key Cryptography [duplicate]

I understand what the two are so need to go into detail about that, however what I'm curious about is in what kind of situations would we use one over the other? It feels to me as if Public Key ...
3
votes
1answer
2k views

Creation and deployment of self-signed certificates for a two-machine scenario

Let us assume that I have two computers: client server Now, in the server computer, I set up a legacy ASMX web service which will going to be used by the client. Before the client can connect to ...