Hello,
The documentation of 'ssh -A' does not mention that the risks can be
somewhat
mitigated by using the '-c' option of 'ssh-add'. In my
experience, people are
unaware of the '-c' option, so I suggest to point to it from the
documentation
of '-A':
Index: ssh.1
==================================================================RCS file:
/cvs/src/usr.bin/ssh/ssh.1,v
retrieving revision 1.345
diff -u -r1.345 ssh.1
--- ssh.1 19 Apr 2014 18:42:19 -0000 1.345
+++ ssh.1 2 May 2014 20:14:18 -0000
@@ -121,6 +121,11 @@
An attacker cannot obtain key material from the agent,
however they can perform operations on the keys that enable them to
authenticate using the identities loaded into the agent.
+Using the
+.Fl c
+flag of
+.Xr ssh-add 1
+can reduce (but not eliminate) the risk.
.It Fl a
Disables forwarding of the authentication agent connection.
.It Fl b Ar bind_address
I'm not married to the specific text in the patch; I'd just like the
documentation of -A to contain a crossref to -c.
Cheers,
Daniel
