OpenSSL is an open-source implementation of the SSL and TLS protocols.

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Why won't Firefox accept my certificate?

I've been trying to get stunnel to work with my signed certificate (with a CA that I've trusted in Firefox). The error is: 127.0.0.1:5559 uses an invalid security certificate. The certificate is ...
2
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1answer
27 views

Can you tell OpenSSH to force a rekey according to a packet number limit?

OpenSSH has a parameter in the config files (ssh_config and sshd_config) for both client and server called RekeyLimit. The default values for it are: RekeyLimit 1G 1h Which will force a rekey ...
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1answer
58 views
+100

X509 CRL suspended certificates and openssl ca comand

In CRL X509 format we have "Hold Instruction code" for a list of suspended certificates. I know that "its use is strongly deprecated for the Internet PKI", but in my own private CA, I want to use it. ...
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25 views

Using the same public exponent for RSA on multiple machines

I have a system where many machines running the same software work independently of each other with no central server of any kind. A user may wish to speak with another user privately and securely, ...
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24 views

How to create RSA host key for OpenSSL 1.0.1 server, with ssh-keygen

Trying to create a private 4096-bit RSA host key, for a server running OpenSSL 1.0.1 using >ssh-keygen -b 4096 -t rsa -f rsa_key when the server starts up, it gives an error about the key, and I ...
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0answers
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Create a signed file from the detached signature and the clear text file content

Assuming I have the following: data.txt data.ps7 (the detached signature) Can I generate the bundled signed file ? Any example would be great, using C#, Java or openssl or any other tool ?
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How do I update a verisign SSL certificate for a website running on Apache for windows server? [migrated]

The site has an SSL cert signed by verisign which expires in four days. Webserver is a windows server 2008 running Apache 2.2. There's an Apache2.2/conf/ssl/verisign folder that has all the certs ...
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1answer
25 views

How is PKCS#10 and x509 related?

I'm unable to make sense of them using the RFCs. Can anyone help? When I use this function, http://www.pyopenssl.org/en/stable/api/crypto.html#x509req-objects , am I creating a PKCS#10 format CSR?
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30 views

What comes into calculation of certificate signature?

I have written my own code with openssl in order to create certificates. In order to verify this code, I tried to reconstruct an openssl commandline generated self-signed certificate ... openssl req ...
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1answer
35 views

OpenSSL certificate revocation check in client program using OCSP stapling 2

Pretty much this is request for additional information for the question: http://stackoverflow.com/questions/9607516/openssl-certificate-revocation-check-in-client-program-using-ocsp-stapling I want ...
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0answers
20 views

Why SMIME decryption works with sender and recipient private key?

Im developing an application, that needs to use SMIME encryption and authentication. I've implemented a decryption system, and am currently testing it. I send the emails with another fully working ...
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How to check if the .sig file is correct? [migrated]

I issued the following commands to create a signature for a file (linux kernel) : openssl req -newkey rsa -keyout codesign.key -out codesign.req openssl ca -config ca.cnf -extensions codesigning -in ...
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1answer
43 views

Can I revoke a client certificate using only it's serial number (not it's crt/pem)?

I've signed and issued some client certificates with my CA. I can now revoke them like so: openssl ca -name ${CA_NAME} -revoke ${USERS_DIR}/${USERNAME}.crt -keyfile $SSL_PRIVATE_DIR/ca.key -cert ...
3
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2answers
66 views

SSL browser session keys

I am trying to export/write the SSL master secret and keys to a file from the chromium browser. I would appreciate if someone could advice me how to do this. To write the premaster secret we can ...
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0answers
62 views

HTTPS: Same certificate, different public key

I have a web server, Debian, and the site uses a HTTPS cert from Thawte. The root certificate meant to be on top of my verification chain is also on the server, in /etc/ssl/certs, because the APT ...
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1answer
65 views

Should 'openssl verify' recognise an exceeded 'Path Length' constraint on a root/intermediate CA?

Background Following the guides here and here I am setting up a multi-level PKI. I have increased the pathlen config to 3, such that I can generate one root certificate that I can use to sign the ...
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0answers
52 views

Modify Certificate Subject using OpenSSL x509 Command

I'm building a CA based on the OpenSSL command line tools. I don't want to use the openssl ca tool and its file based database though, instead I create certificates using the openssl x509 tool ...
3
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1answer
39 views

Do I put my subordinate (intermediate) or root CA certificate in my truststore?

I have a server using a certificate signed by my subordinate (intermediate) CA. My java based client needs to put either the intermediate or root CA cert in it's truststore so when it communicates ...
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1answer
82 views

Monitoring HTTP traffic on openvpn server

I have configured an OpenVPN server and can monitor HTTP traffic via tcpdump. Is there any way to monitor the HTTPS traffic as well? Hints Self Signed SSL certificate as root certificate on VPN ...
3
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1answer
37 views

OpenSSL's EVP functions, more specifically EVP_SealInit

Reference: https://wiki.openssl.org/index.php/Manual:EVP_SealInit%283%29 I want to securely share a symmetrical key between two endpoints using OpenSSL's EVP interface. Transferring the encrypted ...
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2answers
55 views

understanding client certificate - pfx on the general

Today I am given a pfx and told to access a website. I have absolutely no idea what was given to me initially, so please kindly confirm my understanding on a general level 1) the pfx is a container ...
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1answer
33 views

Generate CSR code on local machine

I've tried activating an SSL cert. When it asked for the CSR code, I was thinking about generating this code on local machine because I haven't rented my own VPS yet. The thing is, I'm not sure ...
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1answer
95 views

Why does this key get Base64 encoded prior to use?

I wish to have my server encrypt messages to clients who have each provided the server with an RSA public key, as well as having the clients authenticate their messages to the server using their ...
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0answers
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Openssl ciphers list sorting and removing

I was playing with a ciphers app to create example list of suites. Looking at the website (https://openssl.org/docs/manmaster/apps/ciphers.html) if I run one of the examples there: openssl ciphers -v ...
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2answers
826 views

How secure is AES-256-CBC with user provided password and initialization vector

From my understanding the IV is used as a previous block for the first block only. But since each block is used by the following this adds significant security is a IV is provided and not based on the ...
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2answers
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Use openssl to individually verify components of a certificate chain

This is related to another question, How to verify a signature of one entity by another using OpenSSL CLI? I used openssl s_client -showcerts -connect www.google.com:443 to collect three certificates ...
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1answer
29 views

OpenSSL_encrypt returning an incorrect cyphertext?

I am trying to use the openssl_encrypt function in PHP, this is my code: <?php $message = hex2bin("00112233445566778899aabbccddeeff"); $key = hex2bin("000102030405060708090a0b0c0d0e0f"); $method ...
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1answer
37 views

table elements are not encrypted

I read a security book a while ago that said HTML table elements are sent plain text, even if the server connection is https. Is this accurate? I'm thinking about making an on-line purchase from a ...
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0answers
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About DROWN SSL attack [duplicate]

I need some clarification regarding DROWN attack: 1) All and only SLLv2 is vulnerable regardless of the chipper strength? 2) How can I check it with Nmap or sslscan? 3) How it's done? I have also ...
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3answers
134 views

How to decrypt SSL traffic with a packet sniffer when I have the private key?

How you do you decrypt ssl packets (traffic) with the private key? I tried to do this with ssldump and openssl but nothing worked.
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3answers
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Why doesn't openssl s_client correctly validate google.com:443?

I try $ openssl s_client -connect www.google.com:443 but it openssl complains that the cert chain is invalid: $ openssl s_client -connect www.google.com:443 CONNECTED(00000003) depth=2 C = US, O = ...
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1answer
72 views

How to verify a signature of one entity by another using OpenSSL CLI?

I'm teaching a class about certificate chains, so I download the chain from www.google.com which has 4 certs. I want to demonstrate how the dependencies work from issuer to subject by showing that ...
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5answers
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Is it possible to get the pass phrase for private key file

We have a set of public and private keys and certificates on the server. The problem is that while public encryption works fine, the pass phrase for the .key file was lost. So, when trying to ...
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0answers
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MQTT (Mosquitto) certificate SSL23_GET_CLIENT_HELLO:unknown protocol [closed]

I'm been desperately trying to get my MQTT clients to connect to my MQTT broker which is set up with a certificate from a CA. To be able to get the CA certificate, I've used the letsencrypt python ...
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1answer
44 views

Is reseeding OpenSSL CSPRNG necessary if using RAND_bytes?

I read that cryprographic secure PRNG (CSPRNG) need a random seed to provide random output. Looking at OpenSSL that seems to be archived by RAND_poll() and random data is fetched with RAND_bytes(buf, ...
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2answers
85 views

How to have client encryption without server encryption key

I want to build a service where people can message each other via their mobile device so that they encrypt all of their information on their device and not on my server. Basically I want to two people ...
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1answer
60 views

Regenerating dhparam periodically

Does it increase connection security if I regenerate the dhparam files used with NGINX on our servers periodically e.g. every week? What issues may arise from this? Is there any benefit in doing ...
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1answer
63 views

ECDSA implicit certificate using OpenSSL

I am trying to generate implicit ECDSA certificate only for signing and verification using OpenSSL. I tried google but I am getting many research papers. I understood that A messages need to be signed ...
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1answer
79 views

CSR with only public key with openssl

So I have been doing my research and haven't found anything specific enough to my problem. As the question title states, I want to make a CSR with only the public key. What I have been able to do is ...
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1answer
3k views

How to manually test for DROWN attack?

We know that the official website serves the user with a way to test our servers against DROWN attack. Apart from that, I am looking for a manual testing method to check any servers against this ...
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3answers
98 views

Are there any problems with using CAMELLIA, IDEA and SEED based cipher suites on a web server in 2016?

I have recently seen CAMELLIA, SEED and IDEA cipher suites in use for HTTPS on a web server and am unsure what to suggest to the owner. The keys in use are all over 128 bits in length and standard ...
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1answer
210 views

Cache Bank conflicts and CacheBleed: What is there to worry about?

It seems that researchers have announced yet another vulnerability regarding OpenSSL, separate from the DROWN issue, called CacheBleed. You can view the research paper here. How does it work, and ...
157
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2answers
20k views

What is DROWN and how does it work?

There is a new recent attack "on TLS" named "DROWN". I understand that it appears to use bad SSLv2 requests to recover static (certificate) keys. My question is: How? How can you recover static ...
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0answers
24 views

RSA decryption with Private and Cert files

What I have : The cipher message, the plaintext message, and something that could be the RSA Private & Cert. (I can create as many couple ciphered/plaintext as I want) I would like to be able to ...
1
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1answer
53 views

Protect against client-initiated renegotiation DoS in OpenSSL/Python

According to https://blog.qualys.com/ssllabs/2011/10/31/tls-renegotiation-and-denial-of-service-attacks, servers supporting SSL/TLS connections and allowing client-initiated renegotiations are ...
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0answers
24 views

Finding the EMSA-PKCS1-v1_5 DigestAlgorithm field in the x509 certificate

From the RFC - https://www.ietf.org/rfc/rfc3447.txt A.2.4 RSASSA-PKCS1-v1_5 For each OID, the parameters field associated with this OID in a value of type AlgorithmIdentifier shall have a value ...
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1answer
42 views

How is hash used with AEAD-based ciphers in TLS? [duplicate]

Look at this cipher: ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(128) Mac=AEAD It uses AES-GCM for encryption and data origin authentication (according to RFC-5288), so no ...
3
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1answer
45 views

self-signed CA next to signed CA?

What I'm trying to do is implement client-certificate authentication on my website (running on Apache). From this question I understand that it's not possible to generate a client certificate myself ...
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0answers
26 views

Followup to one-liner to create cert request with SAN

I've been trying to use the OpenSSL line from this older thread to create a CSR with subject alternative name: Provide subjectAltName to openssl directly on command line If I run the line from that ...
1
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1answer
51 views

Is there any way or tool to check whether a particular iOS app is implementing SSL Pinning functionality?

I'm just learning the iOS security. This is completely a beginner question. I'm trying to figure out whether there is any particular way to check if an iOS app is implementing SSL Pinning ...