Questions tagged [cipher-selection]
For questions about the step of the SSL/TLS handshake where the cipher is negotiated between the client and the server. This tag could also be used for questions about which ciphers to support in your application / configuration.
208 questions
0 votes
1 answer
86 views
How do browsers detect ssl_error_no_cypher_overlap(firefox)/ERR_SSL_VERSION_OR_CIPHER_MISMATCH(chrome) errors?
When server sends TLS ALERT: ERROR CODE 40 (FATAL HANDSHAKE FAILURE), how does browser know exactly that it's a cipher mismatch/overlap error? Do the browsers assume/presume it? Or is the only error ...
7 votes
2 answers
4k views
Why are CHACHA20 TLS ciphers not compliant with the NIST guidelines and FIPS/HIPAA standards?
I happen to recall that CHACHA20 ciphers are not compliant with both NIST guidelines and FIPS/HIPAA standards. As used to be stated by htbridge.com SSL tests years ago. I just found similar ...
- 7,715
2 votes
3 answers
273 views
If I control both sides of a connection, is there any reason to support alternate cipher suites?
If I have a system where I have 100% control over the client operating system and the server operating system, is there any use case for enabling more than one cipher suite (or any of the options that ...
- 211
0 votes
1 answer
404 views
Why is ECC (Eliptical Curve) an `--expert` feature in PGP?
Eleptial Curve is now included in PGP. However when I run gpg2 --full-gen-key, I get Please select what kind of key you want: (1) RSA and RSA (default) (2) DSA and Elgamal (3) DSA (sign only) ...
- 3,237
1 vote
0 answers
2k views
Disabling weak cipher suites in Tomcat does not work as expected
I have to get rid of so called "weak security" in a Tomcat application. A penetration test identified services that accept connections with insecure TLS encryption and hashing algorithms: ...
- 161
0 votes
1 answer
258 views
How to create a cipher string that doesn't contain AES and CAMELLIA ciphers?
I am trying to learn about cipher lists and how to order them. I am new to this. I have gone through this doc. I don't get some of the things mentioned in it. Maybe this post can clairfy it. I want to ...
2 votes
4 answers
8k views
Which cipher is more secure TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA or TLS_RSA_WITH_AES_256_GCM_SHA384?
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA supports forward secrecy, but it doesn't use GCM mode, and uses SHA1. TLS_RSA_WITH_AES_256_GCM_SHA384 uses GCM mode and uses SHA2, but it doesn't support forward ...
- 21
2 votes
2 answers
2k views
Cipher suite choice on macOS on Apple Silicon
I have a postfix mail server that accepts these cipher suites: tls_high_cipherlist=ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256: ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384: ...
- 767