Collaborate Disseminate
I am not a security expert, so please forgive me if the question is too obvious. We have been working with Blowfish to encrypt some of our files. We recently updated our very old OpenSSL version from 1.1.1 to 3.0.12 and we found out that B… Continue reading Why is Blowfish Cipher considered now "legacy" algorithm in OpenSSL?
I am trying to see HTTPS traffic in wireshark from my local machine to public sites, just to see how the TLS handshake is made.
Why can’t I see the traffic as HTTP2 in filters and only able to see TLS traffic to port 443 and back to my ma… Continue reading Why Can’t I See Server Certificates in TLS Handshake Public Websites [closed]
I was testing the supported cipher suites for an exposed httpd service.
On the server, the cipher suites are defined in the httpd properties file ( httpd.sslCipherSuite=….)
When I run testssl from my Kali machine, I get a list of cipher … Continue reading testssl not detecting all cipher suites
I have Linux servers, which was reported by IT security team having various obsolete ciphers, and I need to disable them and replace with newer versions if they used by applications. However I stumble, that I can’t even find these ciphers…. Continue reading How to find and disable specific ciphers on Linux?
I received a spam text message and interrogated the domain name:
$ openssl s_client -servername https://example.com -connect example.com:443
What I want to know, is how likely it is that I should see the following
write:errno=0
no peer c… Continue reading TLS1.3 using no cipher?
I’m confused how to retrieve the remaining 8 bytes of the nonce (to combine with the 4 bytes established during the handshake) to generate the 12 byte IV to decrypt AES 128 GCM.
RFC 5288 "AES Galois Counter Mode (GCM) Cipher Suites fo… Continue reading Where is the 8 byte explicit nonce for decrypting AES GCM within TLS?
I’m looking to encrypt some 64 bit integers, with a maximum cipher text size of 128bits. The encrypted numbers will be displayed in some public places, so shorter, "vanity" sizes is a primary design constraint.
It’s not critical… Continue reading How to pick a symmetric cipher for a given cipher text size?
On our Windows Servers, we have disabled the following key exchange algorithms in registry
SCHANNEL\KeyExchangeAlgorithms\ECDH
SCHANNEL\KeyExchangeAlgorithms\PKCS
This leaves us with only 2 available Cipher Suites that could be offered i… Continue reading Enabling ECDH KeyExchangeAlgorithm in Windows Schannel while disabling CBC based ciphersuites
There is a server (app) that uses OpenSSL to allow clients establish secure connection.
The certificate info for server public key is:
Certificate:
Data:
Version: 1 (0x0)
Serial Number: 1 (0x1)
Signature Algorit… Continue reading How server key limits protocols and ciphers used? [duplicate]
I am trying to connect to a server using SFTP protocol
To connect successfully, I had to do the following from the centos terminal.
sftp -o KexAlgorithms=diffie-hellman-group1-sha1 -o Ciphers=aes256-cbc USER_NAME@IP_ADDRESS
Now I want to … Continue reading Curl how to specify KexAlgorithms and Cipher [migrated]