By default, entries in ~/.ssh/known_hosts disclosure on which servers a
user as access to, allowing detailled attack against these servers.
Depending on the affected infrastructure, this might be a privacy
problem, too.

Force SSH to hash new entries in known_hosts (existing ones will not be
converted) to avoid permission disclosure.

Signed-off-by: Peter Müller <peter.mueller(a)link38.eu>
---
 config/ssh/ssh_config | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/config/ssh/ssh_config b/config/ssh/ssh_config
index b36909f85..9f7121c76 100644
--- a/config/ssh/ssh_config
+++ b/config/ssh/ssh_config
@@ -33,4 +33,7 @@ Host *
         # ensure only allowed authentication methods are used
         PreferredAuthentications publickey,keyboard-interactive,password
 
+	# hash entries in ~/.ssh/known_hosts file to avoid permission disclosure
+	HashKnownHosts yes
+
 # EOF
-- 
2.16.4