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by driverdan 4628 days ago
Weak cyphers should be disabled on the server entirely, not just re-ordered.
1 comments

Knee-jerk disabling of RC4 because it's "weak" would almost certainly reduce the security of the Internet, because you can't simply evaluate TLS ciphersuites based on the strength of their core cipher; there are lots of deployed TLS clients that can't do block cipher crypto securely right now.
Examples please?
RC4 was first used as a mitigation for the BEAST blockwise-adaptive attack on CBC-with-chained-IVs from SSL 3.0 and TLS 1.0, and then again as a mitigation for the "Lucky 13" timing-based CBC padding oracle that remains a problem in TLS 1.2 when block ciphersuites are used.
Ok, thank you. I misread - I thought you meant that there were clients which weren't capable of handling block cipher suites (e.g. for performance reasons). You made me look into "Lucky 13" though, so at least I learned something!