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50

In essence, these certificates are necessary and required for backward compatibility with XP and Server 2003. If anything was signed with these certificates, even if they're expired now, your server needs the cert trusted in order to trust the thing that the cert signed. Source: http://support.microsoft.com/kb/293781 Some certificates that are listed in ...


4

When you are browsing TOR hidden services, the TOR system already provides end-to-end encryption, so another TLS layer is redundant. It is in fact counter-productive, because one of the goals of TLS is to de-anonymize the server. It makes no sense to go through the trouble to set up a hidden service and then get a certificate from a certificate authority ...


1

Passwords can be easy to forget. can be easy to guess / crack. can have different contraints in terms of characters you can use, length... are very often re-used on different services. have you heard of those passwords database leaked? Challenge-Response can comprise any amount of challenges (e.g. enter 3 passwords in a row) can support one-time ...


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The general situation looks like this: A signature relies on some certificates, that assert the ownership of public keys. Certificates are primarily designed to be validated now (e.g. the certificate's date of validities are compared with the current date). These objects tend to degrade over time. CRL expire (usually rather fast). Certificates expire; when ...


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Regarding CRLs: CRLs are issued regularly. They don't need -- nor should they have -- long durations between updates. They are regularly reissued. (I just checked Facebooks certificate and they use http://crl3.digicert.com/ca3-g29.crl -- This CRL lists 7 days as the maximum time until the next update.) So you can just sign them with the signature of your ...


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TL;DR - Use SMIME or PGP if you're paranoid of everything. More information: To answer your boiled-down question: How do you secure email? Practically speaking email is subject to attack by DNS spoofing, WIFI interception, and untrusted network administrators just to name a few. To mitigate this you need to consider the different aspects that need ...


4

In general, yes. With many asymmetric cryptosystems, one of the keys can be derived from the other one, so there is no choice as to which one to keep private. Many asymmetric cryptographic algorithms are based on the difficulty of computing discrete logarithms. The private key is an integer k and the public key is the value gk for some public parameter g in ...


11

Shouldn't necessarily matter... In RSA you can use either d (private) or e (public) to encrypt and also decrypt. This doesn't work with all cryptosystems. For example DSA won't allow this. So technically it wouldn't really matter if you exchanged the values of e and d. ...but does Performance: But actually you usually want verification (using e) to be ...


1

Signing will be done by the key only, so as long the key is not changed all signatures done by this certificate are still valid. But, when building the trust chain for a certificate it will look at the certificates issuer field and then search for a certificate having this issuer as the subject. Only after it found a certificate (or multiple) having this ...


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So, how does an Intermmediate CA change one field, without having to reissue every single cert? It does a cross signature with it's old key (--placeholder -- would love to see a great answer on how cross signing works, or I'lll plainly and clearly ask that)


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No, not with regular PKI Could your question also be phrased "If I control a Root CA, can I then limit one of my sub CAs to issue a maximum of, say, 1000 certificates?" -- If that is what you're asking, then "No". There is nothing like that. The root CA is no longer involved with its Sub-CAs after they are created. And it has no way of knowing what the ...


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A sub-CA can manage (in theory) infinite sub CAs, and they too can have infinite sub-CAs There is a way for any parent CA to limit this proliferation, the way to do this is to set the path parameter. This counts how many sub-CAs are available and permitted. For example, if you create a CA that only issues end user certificates, and never another CA ...


5

Recently, our clients want to encrypt their files for one reason: " They don't want FTP server admin has access to their files". With this requirement the encryption should not be done at the server side. Otherwise an administrator could just grab the content before it gets encrypted. And of course the management of the passwords/keys should also be ...


4

My suggestion is to have your clients manage their owns encryption password or certificates. Certain FTP clients will allow the use of encryption, as an example: http://www.coreftp.com/docs/web1/FTP_Encryption.htm. I want to make sure though that you're actually using some type of encryption for the transit of their data. You don't mention it and since ...


1

Some CAs will not allow two certificates with the same SubjectDN, so the new one would supersede the old one. If there is no reason to believe the previous certificate had its PrKey compromised, it does not need to be revoked prior to signing and installing the replacement. Speak to the operators of your CA, especially the personnel acting as an RA, since ...


0

CA or a Sub CA Anything apart from a Root CA may in principle be revoked using the regular ways. (CRL and/or OCSP) [...] they may want to suspend the certificate till the time, they confirm that this is true. Technically you should be able to do this by using reason code "certificateHold (6)" on your CRL. This is a temporary revocation and ...


4

pgp.mit.edu and most other key servers are currently running the SKS key server software, which is (as of November 30th, 2014) not yet ready for the new ECC keys. There is some code, though; but it is not ready for production yet. Be aware that even if most keyservers will support it (probably rather soon), broad support for ECC keys with other OpenPGP ...


1

Is it a must-act-immediately-because-attacks-are-feasible-now? No. That said, when working with PKI, you must have a long vision, so start planning now. It is estimated that by the end of 2017, precomputed hash-collisions to create imposter certificates (and hence imposter CA certificates) may drop below 100,000$ in computation, using cloud computing ...


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If you think a downstream (subordinate) CA is compromised, you have a duty in your position of trust to revoke the suspected compromised CA to prevent them from eroding trust in you, the parent CA.


2

Is this a hot issue for mostly security reasons [...] Not yet. There is no practical published attack yet. But it's in the post. The gradual transition now is better than the transition from the earlier MD5 hashing algorithm to SHA1. Back then there was no explicit deprecation strategy AFAIK and there actually were evil attacks that used ...


2

They are defined in the standard, maintained on the OASIS website...symbols and abbreviations. And the list there matches yours.


0

Firstly, glad you did not suggest designing your own; that way lies years of insecurity and support nightmares. PGP supports a PKI with X509 certificates[1], though few people use it that way. Another option is S/MIME, with certificates issued by a well-known CA[2]. Either way, you get central management of the hierarchy of trust and can skip the headaches ...


0

I don't know if you are looking to "roll your own" solution, or if your business is willing to invest in a commercial product. If you are interested in a commercial product, Voltage Security has "Voltage SecureMail" http://www.voltage.com/products/securemail/ which would meet the needs you've described.


0

Why don’t use just use a tool like IRI FieldShield (works on any DB and flat-file via Eclipse or command line) and apply AES-256 format-preserving encryption as a rule across the SSN and ZIP code columns across your sources? That preserves realism, referential integrity, restricted access, and reversibility all at the same time.


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Most if not all database engines support 'encrypted columns' which securely stores the data, so in this way yes there are tools that do this for you. Next you have the issue of searching based on those encrypted columns. http://dba.stackexchange.com/questions/23908/how-to-search-a-mysql-database-with-encrypted-fields The quick explanation is that you ...


0

To avoid the "not completely implemented" issue mentioned in Jens Erat's answer, use gpg --homedir on a temporary directory. You may need to modify the mktemp command based on your platform: gpg --homedir $( mktemp -d -t '' ) --import /tmp/somekey.asc


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Apologize for posting a question without doing research on my own. Here is how i got around just in case anyone gets into the same bind convert the cert into bytes and then convert to X509Certificate. Then you can do X509Certificate.getSigAlgName(); Thanks Again


1

A key is a key. There is no such thing as a "RSA-with-SHA-1 key". A RSA key that can be used for signatures (using the PKCS#1 standard) will be used in conjunction with some other parameters, including a hash function such as SHA-1 and SHA-256; but there is no intrinsic property of a key that would prevent usage of SHA-1 or SHA-256 as hash function within a ...



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