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A public-key infrastructure (PKI) is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates. In cryptography, a PKI is an arrangement that binds public keys with respective user identities by means of a ...

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21 views

Root CA with Extended Key Usage fields

I recently started using AWS's Certificate Manager to get free TLS certificates for my load balancer. When I was inspecting the certificate chain I noticed that the Root CA, Starfield Class 2 ...
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0answers
18 views

How to detect C2C communications on HTTPS? [duplicate]

I’m apologizing first If this question is very trivial for many of you. HTTPS traffic is encrypted and we cannot see POST and GET artifacts on them. So, if an C2C is using HTTPS, then what are the ...
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0answers
30 views

Product & Feature Comparison of EJBCA, Active Directory Certificate Services, or Entrust Authority Security Manager?

I'm currently beginning analysis in this field and stumbled across the thread titled: "Comparison and difference between CAs" The question seems largely unresolved. Does there exist any product or ...
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0answers
24 views

Bloom filter to prevent replay attacks in signed HTTP requests

I'm thinking about an authentication sheme of a REST API in a setting where the only thing the server stores about a client, is their public key (the asymmetric encryption scheme should not matter). ...
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1answer
18 views

Limit OpenVPN client certificate to specific VPN with shared CA chain

I've created a private x509 pki structure with openssl that consists of a self signed Root CA, an Intermediate CA and two Signing CA's. The signing CA's are used to separate the signing of ...
1
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1answer
26 views

Security Appliance Key Generation

For devices like decrypting HTTPS proxies, there is often a built-in mechanism for generating a key-pair and CSR. An admin can then have their in-house authority sign the CSR with a subordinate CA ...
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2answers
39 views

Does the symmetric key exchange through asymmetric encryption have to be done asymmetrically?

To communicate over a public channel, it seems often that 2 parties first use some asymmetric-encryption way to exchange a symmetric key. And then use the symmetric key for subsequent communication. ...
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0answers
3 views

OpenSC fails to connect javacard with PKCS applet [migrated]

I have empty JavaCOS A40 smartcard and want make it a PKCS PKI card. I'm going to use it as ssh key and for e-contracts signing. Russia don't provide smartcard-based e-id for citizens like EU ...
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2answers
83 views

What is the difference between digital notary and certification authority?

Is the difference purely legal or is there a technical difference between a notary notarizing the document signer's identity and a certification authority certifying a signer's certificate?
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1answer
72 views

Should we use x509 V1 certificate for a new root CA?

I read a couple of articles that kind of gives the impression that the norm is to use a V1 x509 pkc for a root CA. This is one of them. However the rfc5280 makes no such suggestion. My question is, ...
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1answer
56 views

Public / Private Key Cryptography for offline systems

Are there any best practices around distributing an encrypted package to multiple end user systems, specially if the end system are offline ones, in context of asymetric cryptography? Is it a must to ...
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4answers
154 views

How do mobile apps prevent HTTPS MITM attacks when the user installs the attacker's CA certificate?

I am using a mobile app that installs a fake trusted CA certificate and therefore can capture the HTTPS traffic of other apps. Most of the time, this MITM attack is successful. However, I noticed ...
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0answers
50 views

How to auto renew OpenVPN client certificates using easyRSA

I have embedded devices that are located in different cites and connected to my OpenVPN server. I initialize my devices before deploying them and put the certificate/key pair through local network. ...
2
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0answers
32 views

Protecting private keys of common chat applications with 2FA

Say a user uses a common chat application like Telegram, Signal, Whatsapp, Ricochet. His device gets hacked and private keys get stolen. For normal PGP usage with email you can use two factor ...
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1answer
45 views

What happens if my private key gets stolen in the web of trust?

If I'm a trusted user in the web-of-trust but my private key gets stolen by Eve, how would other users find out that my key is compromised and thus cannot be trusted anymore? Is there a way for them ...
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1answer
69 views

Should I distribute Root CA or Intermediate CA certificates to client?

I've been following this tutorial to create a Root CA, intermediate CA, and server certificate. I can verify: the intermediate certificate with the root certificate the server certificate with the ...
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1answer
86 views

Trustworthiness of Let’s Encrypt and ZeroSSL within browsers and OS [duplicate]

With regard to Are there technical disadvantages in using free ssl certificates? it has been highlighted by some that StartSSL is not a trustworthy CA, and I was wondering if Let’s Encrypt is the same....
1
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1answer
67 views

How does blockchain client trust other nodes?

If we consider any blockchain based system (bitcoin, for example), how does initial trust setup works? When a new user wants to join blockchain network, how does the client know that it talks to ...
2
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1answer
70 views

Web of trust jeopardized because servers getting hacked?

I've read that a common way for servers to handle the SSL certificate is that the private key is not encrypted. Now, a many web servers are getting hacked each day. Assumed that the private key is ...
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1answer
55 views

Encrypted log entries authorization

We have a database table of encrypted log entries, each encrypted entry containing information about the user who created the entry. The entry is encrypted with the encryption key of the particular ...
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2answers
84 views

Private Blockchain VS regular Public-key cryptography [closed]

Private Blockchain (permissioned) VS regular Public-key cryptography: What is the need and add-value of a private blockchain (permissioned) if one can use normal regular public-key cryptography?
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2answers
222 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. ...
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2answers
45 views

Usage of same certificate for client and server authentication

Let's assume I have a device that has both client and server applications running on it at the same time. The client application for example connects to a remote secure webserver (HTTPS) that requires ...
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1answer
114 views

Can Apple technically intercept iMessage messages

I'm basing this question off the iOS Security Guide. If I understand this correctly, when you enlist in iMessage, the private key stays on your device, while the public key is pushed to a directory ...
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0answers
29 views

After downloading my private key/public key pair from a Google API service account, where is my public key?

I'm sure there's an obvious answer - I have been searching. I created a Google service account and generated a key. The tutorials say that this creates a public/private key pair. The created file is ....
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0answers
38 views

Client authentication using certificates in M2M communication

We're planning to implement following scenario for a secure machine-to-machine (M2M) communication network. We have some gateways and a lot of secure sensors which should only be able to "speak" to ...
2
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0answers
35 views

Why CA certificate can't be spoofed? [duplicate]

I was trying to learn TLS in depth. Probably my understanding is wrong. This is what I understood: At the end of client handshake, the server will send the CA certificate to the client which contains ...
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3answers
209 views

What kind of IoT devices use certificates?

I have read that PKI certificates are the main way to provide security on IoT platforms. And the common enrollment protocols for certificates are: SCEP (Simple Certificate Enrollment Protocol) EST (...
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3answers
312 views

Where are private keys stored? [closed]

May sound like a silly question but where are private keys stored as part of Asymmetric Encryption? For example say I have a Web Server and I install a 3rd Party SSL certificate from a third party. ...
2
votes
1answer
27 views

Extra EKUs set in client certificate a security risk?

I have implemented a 2-tier Windows AD CS PKI. For 802.1x I'm using autoenroll to distribute computer certificates automatically to any domain joined computer. Currently I use a single computer ...
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0answers
45 views

Mostly offline CA HSM

I am looking at deploying some PKIs for a couple different clients, some big and some small. For cost savings (and other reasons) we are contemplating hosting one or more of the issuing CAs in AWS ...
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1answer
100 views

PKI: why is leaked CA certificate a threat?

According to the SSL/TLS threat model from ssllabs: https://www.ssllabs.com/downloads/SSL_Threat_Model.png Why is "Leaked CA Certificates" a threat? (In the "Trust (PKI)" branch) Isn't the purpose ...
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1answer
95 views

Which type of smart card supports certificates?

For an IT security demonstration I want to set up a small demo PKI including smart card authentication based on certificates generated by a Certificate Authority, using a class 3 pin pad reader. For ...
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1answer
49 views

Why is establishing trust in public key cryptography a harder problem than its computational costs?

In one of our exams for a non security course, the professor asked for one key problem for public key cryptography and explain why is it a hard problem. Several students claimed that the hard problem ...
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2answers
119 views

DRM using embedded private key

I've started learning about cryptography used for DRM solutions, and curious to know if this is a valid solution for a custom embedded system running purchased software assets. ECDSA public / private ...
2
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1answer
978 views

Difference between key encipherment and data encipherment?

In the context of SSL/TLS certificates, what is the difference between key encipherment and data encipherment? What are some examples that highlights the difference?
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1answer
104 views

How do I detect if the public key in a digital certificate is modified?

I know how the basic process of digital certificate, but how do I detect if the public key in a digital certificate is modified?
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2answers
127 views

Self-signed CA and digital signatures

I am asked to design the public key crypto system for an IoT-like devices. These devices are going to be talking to each other over TCP/IP as well as communicating with a cloud-based API server. The ...
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2answers
3k views

Is there any security risk when a certificate authority is used more than all others?

According to NetTrack, Let's Encrypt is now used on more than 50% of domains (51.21% as of April 2018). I know Let's Encrypt helped a lot of people to get free certificates for their websites, so I ...
2
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2answers
59 views

Official trusted certificated entities

I am learning about root certificates entities and I have a few questions about that. As far as I know my browser trust in a root certificates entities and I can find the list in "configuration" > "...
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264 views

cfssl example certificate chain verification failure

I am getting the following error when trying to verify the certificate chain of a dummy root/intermediary/end PKI. root generated as follows: mkdir {root,inter,end} cfssl print-defaults config > ...
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81 views

PKI: How to identify RA & VA in certain HTTPS website?

I've been reading about PKI (Public Key Infrastructure) and was wondering how to identify the following information. There are 3 main components of PKI which are: CA (Certificate Authority ) - ...
1
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1answer
81 views

Is it safe to commit ascii-armored symmetric private key to VCS?

What is the risk of committing an ascii-armored symmetric private key to VCS where the password lives outside of source control? This is a private closed-source repo. Two helpful topics: When can I ...
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0answers
25 views

Implementation of HTTP Public Key Pinning [duplicate]

I am trying to implement HTTP Public Key Pinning and i am having some issues with the certificate. I followed this guide to create the HTTP Response in IIS: https://www.namecheap.com/support/...
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2answers
192 views

IP Security (IPsec) vs Public Key Infrastructure (PKI)

I've found the following question on the internet and don't think the answer is right. Which of the following does IPsec use? A) SSL B) AES C) DES D) PKI The given answer is D, PKI ...
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0answers
134 views

Symantec rooted certificates trust and Oracle Java trust store, is Oracle planing to remove trust as well?

We are using Symantec CA rooted certs to sign JARs. Since Google and Mozilla have indicated that they are not trusting Symantec CA, should I be concerned that Oracle will remove trust from Symantec CA ...
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1answer
430 views

How does SSH know which public key to use from authorized_keys? [duplicate]

When an SSH client connects to an SSH server using public key authentication, the server encrypts a message using a public key from authorized_keys, and the client must prove it can decrypt the ...
2
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2answers
266 views

Storage of certificates and keys in hardware security modules (Use-case TLS)

I am interested in the general security goals for public key cryptography and the different elements of it. Outline of the use-case: My use case is an embedded device, which will use TLS to establish ...
2
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2answers
453 views

Why does WannaCry encrypt symmetric key with a new per-victim-only public key?

According to this answer, WannaCry will: Generate AES key at victim's system to encrypt victim's files. Generate RSA key at victim's system to encrypt AES key generated above. Encrypt private key of ...
2
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1answer
44 views

What advantages would client-side certificates have over signature based auth such as Oauth2 or HMAC for HTTP Requests?

My application currently supports these two authentications methods OAuth2 and HMAC Auth. OAuth2 https://tools.ietf.org/html/rfc6749 HMAC https://tools.ietf.org/html/draft-cavage-http-signatures-09 ...