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1answer
30 views

What's RSA and ECC's role in TLS 1.2? [duplicate]

I'm trying to figure out what is RSA and ECC used for in TLS 1.2 cipher suites. Let's take TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 for example, communication between server and client would look ...
2
votes
2answers
75 views

Openssl ciphers: what does Au=ECDH mean?

I am trying to get a grasp on different stages of SSL. I have referred to some fantastic answers about how SSL/TLS works and specifically about authentication mechanisms, and numerous other sources. ...
1
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0answers
35 views

Why does not ECDHE-ECDSA work? [migrated]

I am now using this ciphersuite: ...
1
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0answers
9 views

Need Help: How to do XML Element Encryption using JAVA? [migrated]

I have a question regarding Java programing. I have this .PFX file that contain public key and private key public key algorithm = RSA public key format = X.509 Public Key = Sun RSA public key, 2048 ...
1
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1answer
77 views

Is CVE-2013-2566 a practical attack against RC4 or still conceptual?

Is CVE-2013-2566 a practical attack against RC4 or still conceptual and does it only apply to WPA/TKIP?
1
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1answer
48 views

How to change personal cipher/digest preferences of existing OpenPGP key in GnuPG?

The OpenPGP key contains a list of personal algorithm preferences (the meaning of the numbers can be decoded in RFC 4880): # gpg -a --export "foo@example.com" | gpg --list-packets | fgrep 'pref-' ...
0
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1answer
122 views

Google Chrome obsolete cryptography

I have a apache server running and following configuration for ssl: Header always set Strict-Transport-Security "max-age=31536000; includeSubDomains" SSLProtocol -all +TLSv1.2 SSLCompression Off ...
2
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0answers
97 views

OpenSSL: Allow CBC ciphers for TLS but prevent for SSL3

In my server application using OpenSSL, to prevent the poodle attack, I added an option to fully allow/prevent SSL3 protocol. SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2); //Prevent SSLv2 ...
1
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1answer
67 views

Choosing a cipher and MAC for an SSH connection

The cipher and mac selection according to this are in some sort of order in a config file. How do the client and server know that they are using the same ones though? Is this information exchanged in ...
2
votes
1answer
243 views

DHE_DSS vs. DHE_RSA

I have been studying to learn about various cipher suites and their performance; I'm wondering about the difference between DHE_DSS_AES256_CBC ciphersuites and DHE_RSA_AES256_CBC ciphersuites. I ...
2
votes
1answer
624 views

Creating a private key with OpenSSL and encrypting it with AES GCM

My goal was to create a private key and to encrypt it with a strong cipher. That key would be used as a root certificate for an internal Certification Authority. However, eventhough openssl supports ...
2
votes
1answer
265 views

Does OpenSSH use export ciphers?

With all of this talk of 'FREAK', no one has mentioned OpenSSH. It implements libraries from OpenSSL (until recently, anyway). Why aren't people talking about this? is there even a way to configure ...
14
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3answers
877 views

Should I worry if my credit card payment processor's server allows only weak SSL cipher suites?

I tested their server using https://www.ssllabs.com/ssltest/ and, apart from the disappointing "B" rating (it handles financial transactions, after all), the server only allows the following two RC4 ...
0
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2answers
137 views

Why use anything other than RSA for transmission encryption?

Being fairly new to the cryptography and data security space, I have sampled a few "Introduction to cryptography" sites/textbooks and they all seem to start in the same general way: This is a Caesar ...
3
votes
1answer
102 views

Does TLS fallback only keep from downgrades to SSLv3?

I have read the RFC on this and can't seem to find what I am wanting to know. When implemented, if a client and a server support TLS fallback protection, does it only keep them from downgrading to ...
0
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2answers
152 views

RC4 support in SSL configuration

GitHub recently improved its SSL setup by removing RC4 support: To keep GitHub as secure as possible for every user, we will remove RC4 support in our SSL configuration on github.com and in the ...
2
votes
1answer
121 views

Can TLSv1.0 ciphers be used with SSLv3?

Can TLS cipher, such as TLS_RSA_WITH_AES_256_CBC_SHA, suites be used within an SSLv3 connection? For example, say the client and server both support TLS but the connection is downgraded to an SSLv3 ...
1
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2answers
1k views

nginx recommended ssl_ciphers

I am looking for some advice on setting the ciphers for nginx with SSL. What would you recommend for a good compromise between security and compatiblity at the moment? I have made some research but ...
3
votes
1answer
657 views

Which forward secrecy cipher suites are supported for TLS1.0 protocols?

May I know which are all forward secrecy ciphers supported in TLSv1.0 protocols?
1
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1answer
111 views

Can TLS fallback work with server side support only?

I have patched my server with OpenSSL 1.0.1j for the Poodle vulnerability. Been reading the spec on TLS_FALLBACK_SCSV. From what I can tell in order for TLS fallback prevention to work properly it ...
5
votes
1answer
676 views

Why does my openssl connection fail with elliptic curve cipher ECDH-RSA-AES128-SHA?

I am using openssl example server and client with specific cipher in ubuntu 14.10 pc. The openssl version is 1.0.1. When I use the RC4-SHA cipher in both sides, the connection is established ...
3
votes
2answers
242 views

Choosing TLS / SSL cipher suites - What considerations are there?

Most of the advice on choosing cipher suites I find tends to be one of these forms: Here's a string to paste into your application, or Here's a list of 30,000-foot generic criteria to use ("favor ...
-1
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1answer
70 views

Calculating the breakability of a given encryption method

I will soon be doing a very important project for school. The main goal of my project is to find a mathematical way to calculate the breakability of a given encryption method of ciphertext. Is there ...
6
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2answers
1k views

Is TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 a safe cipher suite to use?

Is TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 a safe cipher suite to use for a TLS 1.2 connection to a Tomcat server? What are potential weaknesses or better alternatives? I am looking for a cipher ...
3
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1answer
1k views

JSSE recommended cipher suites

In the wake of POODLE I am reviewing the configuration of a number of Tomcat servers running on the JSSE connector. In order to work out what ciphers JSSE supported I wrote a little snippet that ...
3
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2answers
795 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?
1
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1answer
540 views

Poodle - possible to protocol downgrade if SSLv3 is disabled but still have SSLv3 ciphers enabled?

My title pretty much sums it up. If I have: A server with the SSLv3 protocol disabled BUT still have SSLv3 ciphers enabled. Would that mean that a protocol downgrade attack can still occur?
1
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1answer
495 views

Can Cipher Suites defined in TLSv1.2 be negotiated by clients that only support TLSv1.0?

If my server has only the cipher suites enabled which are defined by TLSv1.2 does that force a client to also use TLSv1.2 or else not be able to connect or can the connection fallback to TLSv1.1 or ...
1
vote
1answer
1k views

Add Cipher Suite support to Chrome/ Chromoium?

I would like to know how to add Cipher Suite: TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA support to the new versions of Chrome? Since Chrome v25/26 Google stopped the support of Cipher Suite: ...
7
votes
1answer
10k views

How to disable cipher RC4 in ubuntu 12.04

I have been doing Network Scan for our box and Ncircle reported SSL Server support RC4 ciphers for SSLv3. Based on that I did a search and I plan to add to /etc/apache/conf.d/security the following: ...
3
votes
1answer
1k views

openssl ECDHE-RSA… cipher suite selected while using RSA server cert and ECDSA client cert

The scene: s_server using RSA certificate. s_client using ECC-ECDSA certificate. Client authentication is required (option -Verify set on s_server) Cipher-suite selected after handshake is ...
0
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1answer
899 views

How are TLSv1.0 ciphers negotiated as TLSv1.2?

I'm a little confused about something I am reading in Bulletproof SSL. "TLS 1.2 is the only protocol that allows suites to define their PRFs. This means that for the suites defined before TLS 1.2 ...
2
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1answer
219 views

ECDSA/RSA certifcates and cipher selection

In this image can someone tell me if a standard RSA certificate can support the EC*_RSA ciphers listed? If so do you create the typical RSA keys when you are creating the CSR? Also I am fairly ...
2
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1answer
213 views

Drawbacks to only using TLS 1.2 ciphers in OpenSSL

I understand you would not want to do this as it would limit compatibility for older devices and platforms. However if someone were in an all TLS1.2 environment, say a very well managed internal ...
1
vote
1answer
777 views

Display browser requested cipher suites from OpenSSL

I installed OpenSSL locally and used s_server command to start a server by using self signed certificate created by OpenSSL as well. The command I used to start a https server is OpenSSL> s_server ...
1
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1answer
1k views

Using AES as a Stream Cipher

I need to send a lot of small messages that are usually between 128 bits and 256 bits long, and each message is encrypted with a separate 128 bit AES key. Therefore, to send each message with the key ...
5
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1answer
679 views

How did SSLv3 get AES?

IANA maintains a registry of TLS cipher suites at TLS Parameters. TLS provides TLS_RSA_WITH_AES_128_CBC_SHA, its value is {0x00, 0x2f}, and its available in TLS 1.0 and above. The AES cipher suites ...
0
votes
2answers
112 views

How secure would this method be considered for password storage

Ok I am currently storing the passwords in most secure way I could think of. With use of Encryption and Hash. The passwords are first generated by user as plain-text with minimum length of 6 ...
0
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1answer
838 views

Openssl ciphers SHA384 and AEAD

When running the command: openssl ciphers -v I get a long list of cipher combinations. I'm having issues interpreting some of them. An example is: DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH Au=RSA ...
1
vote
3answers
129 views

Is it possible to stack encryption algorithms with SSL?

SSL supports a number of ciphers, but is it possible to stack/nest the ciphers, and process the plaintext in stages? My adversary may be able to easily crack one or more of the stages, but to decode ...
1
vote
1answer
953 views

What is default mode for AES encryption [closed]

What will be the default mode for AES encryption if we don't use any specific mode like ECB, CBC, OFB, CTR, etc. and just carry out the encryption without specifying any AES encryption mode.
1
vote
1answer
4k views

Which is the Best Cipher Mode and Padding Mode for AES Encryption? [closed]

As per PCI-DSS 3.4 requirement: For storing Credit Card Data Strong Cryptography should be used. I decided to use AES Encryption which is a strong and mostly recommended crypto for encrypting ...
0
votes
0answers
21 views

What SSL/TLS ciphers do each version of Android support? [duplicate]

What ciphers do each Android device support? Update: More specific not SSL or TLS versions but the actual ciphers such as ECDHE-ECDSA-AES128-GCM-SHA256, etc. Android 2.3? Android 3.x? Android ...
55
votes
4answers
44k views

“Optimal” Web Server SSL Cipher Suite Configuration

Over the last couple of years there have been a number of changes in what would be considered an optimal SSL cipher suite configuration (e.g. the BEAST and CRIME attacks, the weaknesses in RC4) My ...
1
vote
1answer
210 views

Block Cipher Pseudocode

Suppose that I have a block cipher whose key size is 128 bits. but the block length is eight bits. Let E(m’) be an encryption oracle that encrypts by running our “short” block cipher in CBC mode. ...
1
vote
1answer
354 views

Why does not GSM use any stream cipher mode (OFB, CFB)?

If I understand correctly GSM uses A5/1 stream cipher. My question is why doesn't it use a stream cipher mode like OFB or CFB?
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2answers
518 views

Forward secrecy for kids

In the Scouts, it is popular to use secret codes to write messages (which are simple ciphers). I want to introduce Forward secrecy to the kids so they can use it with these ciphers. So, if the ...
11
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4answers
15k views

Identify and disable weak cipher suites

i'm asking a question on a subject that is pure chinese to me..sorry in advance A security scan result prior to the deployment of a web application on windows server 2008 R2 has raised the below ...
4
votes
1answer
268 views

Are all cipher suites with rc4 in them intrinsically flawed?

I've been wondering lately if RC4 is so flawed in all its forms, why is it that it is still being supported by all major browsers per default? Why does the typical chrome browser prefer ...
3
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2answers
355 views

For DHE_RSA_.. Cipher Suites what is RSA used for?

In addition to achieving PFS with DHE, we want as little as possible to be revealed when the server's private key is revealed. So, what is RSA used for in DHE_RSA cipher suites? What does the server ...