Questions tagged [handshake]
The handshake tag has no usage guidance.
56
questions
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1answer
12 views
TLS- Key exchange for session keys. Why?
I have a question about the Key Exchange Algorithm used in TLS process.
I have read that the Key Exchange algorithm is used by client and server to exchange session keys.
Do the client and server ...
1
vote
1answer
44 views
Is it possible that a single handshake can have 2 TLS versions included?
I am seeing different TLS versions (1.3 and 1.2) in the handshake and intermittently it fails with this error:
TLSv1.3 (OUT), TLS handshake, Client hello (1):.
2020-05-28T14:44:00Z.664 [thread-...
0
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0answers
72 views
Not able to capture 4 way handshake using airodump-ng
I am not able capture 4 way handshake, I also tried manually disconnecting and reconnecting my device to the network in hope that airodump-ng will capture the handshake but no luck. I checked the ...
0
votes
1answer
51 views
How does client verify the certificate provided by the server which is signed by different intermediate CA
I am creating a c++ secure client-server application using openssl library. I am still not clear about some aspects of the SSLHandshake procedure
I have enabled Mutual TLS in-order verify the both ...
1
vote
0answers
38 views
How does BLE secure connection ensure man in the middle protection?
I understand BLE secure connection pairing mode is improvement over Legacy Pairing. The issue with legacy pairing was intial TK value can easily be bruteforce by an attacker.
In contrast, in secure ...
0
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1answer
52 views
What is the role of leaf certificate private key In TLS handshake [duplicate]
What is the role of leaf certificate's private key if this certificate is signed by the intermediate certificate's private key and the certificate signature will only be validated using its public ...
1
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0answers
56 views
How are symmetric encryption algorithms tracked once handshake is complete in common secure communication protocols?
My understanding is that most secure web communication protocols ultimately want to agree on a symmetric encryption algorithm to use for sending and receiving data. Once an algorithm is agreed upon by ...
0
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0answers
100 views
Failed SSL Handshake due to IP change and session resumption
Is using the source IP address in generating the session ID by servers common? I've seen this behavior with a banking website. You visit the website with IP 1.1.1.1, SSL session is generated and used ...
0
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0answers
24 views
Where the certificate public and private keys take a place? [duplicate]
I was reading this topic which talks about the handshake process and key exchange
https://www.ibm.com/support/knowledgecenter/en/SSFKSJ_7.1.0/com.ibm.mq.doc/sy10660_.htm
The article says that the ...
2
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0answers
39 views
Which messages are included in (D)TLS Finished message's verify_data field for session resumption
The https://tools.ietf.org/html/rfc5246#section-7.4.9 states which messages are included for PRF computation that is included in Finished messages
It is clear for 'regular' (initial) handshake
But ...
1
vote
1answer
77 views
TLS 1.2. Handshake: Where do Client and Server negotiate how the master key is built from randoms and pre?
I am currently trying to solve an exercise where I should look at a TLS 1.2 handshake trace while having access to pre and both randoms (server random and client random).
In order to decrypt ...
3
votes
1answer
65 views
TLS 1.2 Handshake: Does the server have to take all extensions sent by the Client?
I am unsure about how extensions are handled in TLS v1.2.
During the handshake, the client is able to add some extensions during ClientHello. As far I understood, the server can pick arbitrary ...
0
votes
1answer
66 views
Is Certification path construction algorithm needed for SSL/TLS?
In the TLS Handshake a Certificate message is sent. This message contains the (chain of) certificates needed to validate the provided certificate of the communicating party.
However, I have also ...
0
votes
1answer
83 views
SSL server sends wrong certificate when accessed via Java
In my project I have to integrate with another system which uses quite specific SSL (and also specific cipher suite).
Here's what I mean.
Whenever I try to access the server with Java (send a request)...
2
votes
1answer
111 views
Does the SSL record protocol encrypt the handshake protocol too?
As I know the first communication protocol which establishes between client and server in SSL is handshaking protocol and as this site says:
The SSL record protocol is used to transfer any data ...
1
vote
1answer
52 views
Does a TLS client needs to support one of the named groups (curves?) supported by the server for TLS handshake to succeed?
Does a TLS client needs to support one of the named groups (curves?) supported by the server for TLS handshake to succeed?
Longer version:
I'm running a web site using Windows Server 2016. The web ...
2
votes
2answers
84 views
Handshake without asymmetric encryption
One of my teacher said "Without asymmetric encryption, we would be forced to use third-party to initiate any connection".
I don't understand how it can be possible, what if an attack occur during the ...
0
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0answers
15 views
Which part/step of the TLS handshake is essential for providing PFS? [duplicate]
I would say the key exchange part, because PFS is used only during the key exchange of server and client.
Am I right or have I overlooked something?
1
vote
1answer
102 views
TLS handshake random bytes reused
What would happen if the random bytes provided by the client and the server in the first two messages would be reused by one peer/by both peers?
I think it would highly reduce the provided security, ...
0
votes
1answer
83 views
SSL Handshake problems
I captured my network traffic to a web server and the SSL Handshake consists only of two packets.
Why does that happen and why aren't there all the other packets?
1
vote
2answers
869 views
SSL handshake not visible in Wireshark
In my organization we have a cloud proxy that work on a loopback address. The vendor of this proxy has deployed an app on our machine which listens on the loopback address.
I have captured the apps ...
18
votes
3answers
5k views
Can attackers change the public key of certificate during the SSL handshake
The communication is not encrypted during the SSL handshake. If an attacker conducts a man in the middle attack between server and client to capture the certificate, and change the public key in the ...
2
votes
0answers
478 views
Airgeddon-ng Handshake fail [closed]
I've followed the following instructions below. This is a freshly installed Parrot OS, not using VirtualBox and etc. I am also using Alfa AWUS036NHA wifi adapter.
ifconfig
sudo airmon-ng start wlan1 (...
1
vote
1answer
103 views
how are symmetric keys generated in TLS [duplicate]
My confusion stems from reading that TLS handshake uses some kind of Diffie Hellmann, when I was certain that the symmetric key was generated by a digest of earlier packets encrypted with clients ...
0
votes
1answer
66 views
Do wifi access points and routers get some kind of data from devices when a device is able to see them?
I was wondering if when a router is broadcasting its signal, it is able to handshake with devices that are wifi enabled and looking for a wifi network to connect and get some info from them?
2
votes
1answer
77 views
Is it possible to setup 1-way TLS client authentication without server certificates?
Is it possible with TLS to only authenticate the client? In other words can one-way TLS be setup in such a way that only the host initiating the connection uses a client certificate and the second ...
1
vote
1answer
427 views
TLS-Handshake, Server Key Exchange, Diffie-Hellman: Where does key length come from?
Where does the key length come from?
In this example it is 2048 bits long:
Secure Sockets Layer
TLSv1.2 Record Layer: Handshake Protocol: Server Key Exchange
Content Type: Handshake (22)...
3
votes
1answer
167 views
Authentication handshake between two independent apps
I need help on a solution for below scenario from a security perspective.
Scenario:
There are two independent web applications App1 and App2.
User will log in to App1 by performing authentication ...
-2
votes
2answers
754 views
Interpreting SSLLabs Handshake simulation results
While testing SSL/TLS details on ssllabs.com for a website, the Handshake Simulation part contains:
TLS 1.2 > http/1.1
TLS 1.2 > h2
For eg:
What do these things mean? I couldn't find it ...
1
vote
2answers
133 views
Key reinstallation attack how does it work without a pre-shared key?
The author of the key reinstallation attack released scripts on Github to test AP and clients.
To test the clients, you have to connect to a fake AP but you still need to know the pre-shared key. Of ...
0
votes
0answers
507 views
TLS Pre-master key [duplicate]
If I have access to the pre-master key of a TLS handshake, is it possible to decrypt the rest of the handshake following this?
If so, is it possible to get the pre-master key while it is still not ...
0
votes
1answer
158 views
Can do I brutefore wifi password with handshake without wifi detection? [closed]
I have captured handshake but now I want to bruteforce wifi without detection it (in different place). Is it possible? If yes, how to do that?
0
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0answers
49 views
Identify SSL invalid handshake using Wireshark
I am doing a research on "Network flow anomaly detection" and use Wireshark for my work. I have a problem of identifying the packets with invalid SSL/TLS handshakes. Is there a way/algorithm to detect ...
3
votes
1answer
292 views
Is it possible to make HTTPS 0-RTT with help from DNS?
This article gives an implementation of encrypted SNI where a public key is retrieved from the DNS. It feels like cheating but imagine this: If the server publishes its certificate on its DNS record, ...
0
votes
1answer
195 views
How does Authenticator gets the PMK which is used to calculate PTK?
I am trying to setup a Supplicant- authenticator and AAA server to perform EAPOL mechanism.
I am able to successfully completed the EAP authentication procedure but 4-way handshake was not initiated ...
2
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0answers
84 views
WPA technical doubts (3)
This is the third post about the set of doubts that came up when I tried to understand WPA3. I am new to this world of cyber-security so every bit of help is welcome!
Someone told me that in WPA2 ...
0
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1answer
1k views
Finding wpa2 key length
Is it possible to determine WPA key length through a successful handshake?
Below is a screen capture showing the packet capture session of interest as displayed in Wireshark:
My question came from ...
2
votes
2answers
5k views
What is the Session ID parameter indicate in Client Hello and Server Hello messages
I was trying to understand the TLS handshake in depth. I set up Wireshark and captured the github.com traffic. While inspecting the Client Hello and Server Hello, I found a parameter Session ID.
...
2
votes
1answer
193 views
TLS 1.2 Missing Finished Message
I'm setting up a TLS connection for the purposes of sending secure SIP. The remote gateway (Twilio) doesn't always send a finish message and as such those requests fail. Everything else appears to ...
1
vote
2answers
1k views
Where is Hashing Used in the TLS Handshake
I understand the basic steps in the TLS handshake. My question is, where and how does one-way hashing fit into the steps below? Is it the session key that is hashed? Many texts mention that the ...
0
votes
1answer
98 views
How SSL Handshake recognise any attack
I already know that a replay attack on an SSL handshake is ineffective, but if we suppose that an "intruder" has listened and has got all of the information from a previous handshake, how will the ...
1
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0answers
191 views
Why WPA2 did not design a PTK based on asymmetric cryptography?
I was shocked to learn how the PTK is crafted from the PMK in WPA2 WiFi.
PMK is made with crypt_hash(SSID + PSK). OK, seems good.
Then, the client and the Access Point (AP) make the famous 4 way ...
1
vote
2answers
656 views
Do TLS standards require the server-side preference to always be used when negotiating ciphers to use?
Someone told me the other day that the TLS standards require the server-side to always have the authority to decide which mutual cipher to use when negotiating with a remote client.
This makes sense,...
2
votes
0answers
69 views
What forces SSL exchange to require my smartcard to finish handshake
First, I hope that this is a legitimate question because it is spawned by what I am experiencing and what is happening. The environment is as follows... I have an apache reverse proxy, that I stood ...
3
votes
1answer
533 views
What are the factors making a WPA2 handshake suitable for cracking?
Days ago I was dumping handshakes of my APs using airodump-ng. I would later use aircrack-ng to crack them using wordlists which would purposely contain the passphrases. However, I noticed that some ...
0
votes
2answers
193 views
Why not encrypt TLS handshake?
this is my first question here, I've researched this briefly but couldn't find any satisfying answer.
TLS handshakes are being sent over the wire unencrypted. This way someone that eavesdrops can ...
2
votes
1answer
302 views
In TLS 1.3 handshake, can an internal error at the client be interpreted as a decrypt error at the server?
In TLS 1.3 handshake protocol, the client sends the ClientHello message to the server. The server then sends back the ServerHello message followed by some encrypted messages. The client then computes ...
4
votes
1answer
181 views
Circumventing Netflow's visibility on SSL traffic
In a SSL handshake, the hostname is visible most of the time as it is needed to validate the certificate over HTTP. Netflow is thus able to pick up the common name from the certificate exchange, ...
1
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0answers
480 views
SSL/TLS handshake potential vulnerabilities [duplicate]
After handshake one could be assure that data are encrypted and secure.
But before that, handshake parameters are transferred via not secured channel. One could be MitM during the handshake procedure....
1
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0answers
272 views
what is the logic in choosing a certificate chain during a “server-hello” message in a SSL/TLS handshake
In a client-server ssl handshake, my server sends a certificate chain back to the client in a server-hello message. But I want to understand as to how that particular certificate chain is getting ...
