Collaborate Disseminate
I am using the same certificate x509 from a web server to encrypt text strings using something like:
openssl smime -encrypt -aes-256-cbc -in input.txt -out output.txt -outform DER server.crt
For decrypting the file:
opens… Continue reading how to renew an expired certificate used to encrypt/decrypt files
What happens when the timestampers certificate expires?
If the code is now untrusted, can it be re-stamped without re-signing?
If not, what good does this timestamp do me if my cert is valid until the same date?
TimeStamperCertificate :… Continue reading What happens when the timestamper’s certificate expires?
After reading a blog post about the new Roughtime protocol, I am not convinced of the original premise that shorter certificate lifetimes increase security. The claim is that a shorter time somehow reduces the exposure if a secret key is c… Continue reading How do short lived certificates increase security?
I couldn’t find such a standard which mention about TouchID or fingerprint log in expiration date.
Suppose I have an application and allow users to log in using the fingerprint. I would like to know for how long should I all… Continue reading When should TouchID/Fingerprint log-in expire?
OTP can be implemented either using Google Authenticator or by sending SMS to the user. The GA code is created using a timestamp and the code expires if it’s used after some time.
However, in case of SMS, the OTP value is saved in the dat… Continue reading Why is the need to expire OTP?
RFC 5280 says:
“The removeFromCRL (8) reasonCode value may only appear in delta CRLs and indicates that a certificate is to be removed from a CRL because either the certificate expired or was removed from hold.”
My question… Continue reading Certificate revocation with reason code removeFromCRL
When I see the warning on my browser about “Invalid Certificate” or “Untrusted Certificate” , I might have doubt about a MITM attack at my network. Should I have the same concern when I see that the certificate expired warnin… Continue reading How can an expired SSL certificate make the server and/or client vulnerable to MITM attacks?
I’ve been looking, but I think its impossible to find a pairing solution that has the benefits of authorization expiration and renewal (like x509 cert expiry and OAuth expires_in), but that works without a reliable clock.
I … Continue reading Authorization expiration without reliable clock / time
I have always considered this a bad practice, although it’s true it’s not a big issue because any software that depends for something important on dates is mostly gonna work using a reliable source to get the date, on the rar… Continue reading Why is it allowed to change dates to absurd values in OS?
I have an app which uses an asymmetric key for encrypting/decrypting data between devices.
However, these devices should no longer be able to decrypt after a certain period of time.
Currently, I’m generating the keypair in … Continue reading Embedding expiry dates into keys possible?