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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39
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1answer
2k views

Why does Windows Ship with Expired SSL Certificates?

I am cleaning up the certificate stores on my Windows machines, and considering which certificates I should keep, and which ones I should delete. Why does a fresh install of Windows Server 2012 R2 ...
0
votes
1answer
722 views

What is the deal with Valicert SSL root certificates?

Does anyone know what the status of the "Valicert Class 2 Validation Authority" root certificate is or what's going on with Valicert in general? I've heard that that cert has been deprecated, no ...
0
votes
0answers
9 views

Build set with PKI from reliable broadcast / random beacon [on hold]

I am trying to build a protocol (or find an existing one) for creating a set $S_2$ with PKI from a set of parties $S_1$ that initially does not know anything about the other parties. We assume ...
4
votes
2answers
166 views

Using a verified certificate to sign others

This relates to PKI and certificates generally but websites more specifically. Could you get a verified certificate from a CA that is signed and fine for use, and then use it to sign your own ...
9
votes
1answer
142 views

Is TLS in Tor useless?

I am trying to optimize the Orchid Tor client library for my needs and noticed that every connection with every node uses TLS with turned off certificate verification. Actually there are no TLS ...
1
vote
1answer
107 views

OpenTSA and PKCS11

We are planning to implement the time-stamping service (RFC 3161) using OpenTSA and we wanted to know: Does OpenTSA support PKCS #11 (Cryptoki) to talk to HSMs? BTW: I did not find documentation or ...
11
votes
4answers
5k views

SSH password vs. key authentication

I've usually been told that public key authentication is strongly preferred over password authentication for SSH. However our previous admin was against public keys and only issued passwords and took ...
1
vote
1answer
638 views

Generating ECDSA certificate and private key in one step

Similar to how it can be easily done for RSA: openssl req -x509 -nodes -newkey rsa:2048 -rand /dev/urandom -keyout example.key -out example.crt -days 365 I'd like to generate a ECDSA cert/key in ...
1
vote
0answers
27 views

Use of RSA in Yaksha Security System

So I'm reading over the Yaksha Security System and see it is based on the RSA cryptosystem and a centralized server, easy enough. What I'm slightly confused on is the math behind the related keys. It ...
59
votes
4answers
39k views

What is certificate pinning?

I'm superficially familiar with SSL and what certs do. Recently I saw some discussion on cert pinning but there wasn't a definition. A DDG search didn't turn up anything useful. What is certificate ...
0
votes
2answers
32 views

SHA1 - S/MIME and CRL validity after deprecation?

In an internal PKI using SHA1 for hashing, will S/MIME signature and CRL/ARL signature be considered invalid in the next few years (SHA1 Deprecation) ? End certificates can be revoked, CA ...
16
votes
3answers
25k views

Expired SSL Certificate Implications

What are the security implications of an expired SSL certificate? For example if an SSL certificate from a trusted CA has expired will the communication channel continue to remain secure?
0
votes
0answers
37 views

How should I organize my keys?

Suppose I have a set of computers with variegate level of trust (for example): I fully trust my own desktop pc at home I trust a bit also my smartphone, but I know it could be stolen I trust a bit ...
2
votes
3answers
63 views

Email Encryption

I'm hoping someone can point me in the right direction. If I wanted to implement email encryption within an organisation what would be the best way? I've been searching the web tonight but all my ...
13
votes
2answers
1k views

Does it matter which key is considered private and which public?

Mathematically, is there a difference which set of characters is private_key and which one is public_key? @Edit At the moment of asking I was thinking on RSA, not asymmetric crypto in general.
0
votes
1answer
95 views

How can I generate some public and private keys on both sides with low overhead?

We have an Authority Center (CA) generating some public and private keys for each client (more than one pair for each client). One method for sending keys to client is sharing a secret key between CA ...
0
votes
0answers
36 views

Is ADCS overkill just to replace self-signed certs?

Several of our internal applications are either not using SSL certificates, or are using self-signed certificates. I wanted to utilize ADCS to create a trusted, internal-only root CA that our browsers ...
0
votes
2answers
37 views

Certificates - What about signing again Intermediate CA certificates?

I an thinking about this issue and it is hard to estimate technical impacts. For any relevant reasons, one want to modify one the x509 field of an intermediate CA. This intermediate CA was signed by ...
1
vote
2answers
37 views

Subordinate Certification Authorities and managed certificates

How many different certificates can a subordinate certification authority manage? Please, supply me also some reference. Thanks
-1
votes
2answers
71 views

Encrypt files on FTP server

I have a practical situation here, my company is a FTP server provider for some clients. The clients are sharing their files on our FTP server and have had no problem with access management and ...
0
votes
1answer
48 views

PKI - Security concerns when changing a certificate hash algorithm

Suppose I want to change the hash algorithm used for a certificate signature (ex: SHA1 to SHA2). Is it better to revoke the previous certificate and issue a new one with expected hash algorithm ? Or ...
1
vote
1answer
131 views

Automate the process of giving a user access to his encrypted messages, when the user loses his password

I'm implementing a way for users to share messages with other users. All users and admin-users have a unique key pair. A message can be sent from one user to multiple users. Admin-users, who always ...
0
votes
4answers
83 views

Temporarily suspending a Certificate Authority's Certiticate

The PKI RFC talks about revoking or suspending certificates. It also talks about revoking CA certs. However, I could not find anything about whether a CA or a Sub CA's certificates can be revoked or ...
2
votes
1answer
74 views

Why can't I upload a new ECC key to key servers, which is supported by GnuPG 2.1?

My OpenPGP key is soon to expire so I wanted to create a new one. GPG 2.1 came out a month ago including ECC support and I wanted to try the new key types. So I have generated a brand new ed25519 ...
3
votes
2answers
60 views

Corporate PKI - SHA1 deprecation

Here is the context. Suppose you have a corporate PKI with : AC_Root (offline in safe store - SHA1 signature) SubRootA and SubrootB (offline in safe store - SHA1 signature) SubSubRootC, SubSubRootD, ...
1
vote
1answer
23 views

Definitions of PKCS#11 abbreviations

Is there a complete definition list for all CKx abbreviations in PKCS#11? I believe I gathered most of them: CK = Cryptoki CKA = ... Attribute CKC = ... Certificate type CKD = ... Key derivation ...
0
votes
0answers
52 views

Why is the public key extracted from the CSR different than the one extracted from the associated certificate?

I am playing around with pyopenssl. I am trying to extract the public key from a CSR and to check if it is the same than the one I find in the associated certificate. There is a small difference ...
1
vote
4answers
87 views

Data anonymization/ encryption requirement

I did check out the previous postings and didnt find what I was looking for- apologies if this is a repetition. I am working on an analytics engagement for a customer and he needs to share access to ...
2
votes
1answer
60 views

Must the distinguished subject name of an issued SSL Certificate match that of the generated Certificate Signing Request?

For example: from Issued SSL Certificate: CN = abc.com.my, OU = Room, O = House, C = MY from generated CSR: CN = abc.com.my, OU = Room , O = House, L = KL, ST = KL , C = MY Is it legal for a ...
1
vote
0answers
190 views

If even Apple cannot properly install certificate [closed]

I've just installed a new copy of Mozilla Firefox/29.0 SeaMonkey/2.26.1 on a new Mac with OS X 10.9.4, and I'm getting an error message in place of a webpage when trying to access ...
2
votes
1answer
239 views

Making a bitcoin-like secure mail protocol, how to tackle public keys?

I'm making a new mail protocol (probably already exists, but I've learnt a lot of things about security and privacy on the way). Here's the summary(much simpler if you know bitcoin's inner workings): ...
3
votes
3answers
2k views

Extracting the PGP keyid from the Public key file?

is there a way via an CLI tool or some kind of API to extract the PGP KEY ID from the PGP PUBLIC KEY BLOCK ? I did find the hexa value of the key in the binary file, however I guess the position is ...
1
vote
2answers
173 views

Certificate security in intranet environment?

We have this topology in our company: A new rule says that each document being sent by Outlook should be encrypted. We decided using PGP. We already have a certificate (self-signed). The problem ...
1
vote
3answers
133 views

What is the web of trust?

I'm studying network and system security and I came across the phrase "web of trust". From Wikipedia: In cryptography, a web of trust is a concept used in PGP, GnuPG, and other ...
-2
votes
2answers
37 views

Get the Signature algorithm from a public key? [closed]

When I do PublicKey.getAlgorithm(), it only returns me RSA. Am looking for something to return Sha1RSA. Basically to identify if it is a sha1 or sha2 algorithm. Any help is appreciated. Thanks,
1
vote
1answer
93 views

Authenticated Diffie Hellman Key Exchange

It appears that the textbook version of Diffie-Hellman is susceptible to man in the middle attack and the use of digital signatures could prevent this attack from occurring. Digital signatures could ...
1
vote
1answer
49 views

What happens if my signing subkeys are compromised?

Let's say my subkeys are compromised, but my master keypair is safe and secure, so I revoke the old subkeys and issue new ones. With encryption keys, the results are pretty clear: I can still decrypt ...
4
votes
3answers
152 views

Anonymiszing sensitive data in MySQL DB while retaining searchability [closed]

I have a MySQL database that stores sensitive (personal) data about individuals; and have been tasked with ensuring that this data is encrypted in some way to protect the individuals and their data if ...
2
votes
1answer
239 views

Bastion host that allows jailed users to SSH but protects private key

Basically, I'm trying to let the user use a private key without having read access to it. Use case: Employee needs to SSH to a server in the data center. There is 1 private key for all servers, ...
4
votes
1answer
64 views

How long do keys stay on keyservers?

Do GPG/PGP keyservers "garbage collect" old keys which have expired, been revoked, or simply haven't been updated in a decade? Or does the server (theoretically) keep every key it has ever seen from ...
1
vote
1answer
31 views

How to understand socat certificate check limitation?

I have set up a certificate-based connection with socat using this tutorial: http://www.dest-unreach.org/socat/doc/socat-openssltunnel.html My socat connection works as following (only the relevant ...
-1
votes
1answer
66 views

How is PKI used to encrypt an e-mail for multiple recipients?

My understanding is that when an e-mail is encrypted and sent to a recipient, the recipient's public key is used to encrypt the e-mail, and then only the recipient can decrypt it with their private ...
1
vote
1answer
334 views

SSL interception with Burp Suite using Firefox - Strange behavior when intercepting twitter

I am learning Burp Suite(Free Edition v1.6). I have set it up with the default settings. The proxy listener is listening to 127.0.0.1 on port 8080 and Certificate option is set to 'Generate CA-signed ...
0
votes
1answer
233 views

How can the private key be obtained in PKI without alerting a third party? [closed]

For example, I sent a message to Ardi and encrypted it with Ardi's public key. Ardi must decrypt the message with his private key. How can Ardi's private key be obtained in PKI without anyone else ...
2
votes
2answers
70 views

Distributing public keys; with or without a sub-key?

Most of the public keys I am getting from friends have a sub key in addition to the pub key. For educational purposes I retrieved some public keys and came across this Linus Torvalds' key that does ...
1
vote
1answer
126 views

Chat encryption system avoiding protocol sniffing and then key+decryption replay?

I'm working on a chat system and I want to add it some kind of security (not just HTTPS with SSL since I've read it can be sniffed and decrypted with a few tools). Now, my knowledge in cryptography is ...
0
votes
1answer
75 views

Shall I set “RSAAuthentication yes” in sshd_config if I use only ECDSA key?

In a context of proprietary client boxes and servers, I want to limit authentication to ECDSA keys. Historically, "RSAAuthentication yes" was used to enable authentication with RSA and maybe DSA keys. ...
4
votes
2answers
3k views

Is your PGP passphrase used to decrypt an encrypted private key, or needed in conjunction with the private key to decrypt the message?

If the former, then if the private key can be used to digitally sign messages, why doesn't your client offer to encrypt this highly sensitive piece of data? If the latter, then if someone had access ...
3
votes
1answer
394 views

Reset Windows trusted certificates store to its default

Over the time I have installed several additional trusted CA certificates to Windows trust store, sometimes because an app pushed me to do so, some other times for development and testing. Is there ...