Bug #4453
closedSquid-in-the-middle SSL Bump downgrades client SSL/TLS connections
0%
Description
When enabling the Squid-in-the-middle SSL Bump option on pfSense 2.2/2.2.1 the SSL/TLS connections between server <-> Squid and Squid <-> client can be downgraded to low secure SSL/TLS ciphers and key sizes. The configuration UI does not allow setting the cipher selection for the "cipher=" option of https_port and neither for the sslproxy_cipher parameter. This essentially lets Squid use a default cipher selection which is a trip back to the 1990s. The SSL/TLS connection(s) suddenly allow 40 bit keys, RC4, and everything that has already been broken.
This is a critical bug and may render strong encryption useless once SSL Bump is deployed. Please use sane defaults for the "cipher=" option of https_port and the sslproxy_cipher parameter. I use the cipher string from https://bettercrypto.org/ and can recommend everyone to do the same.