From a8b5ec5c28805f0ab6b1b05474531521ac42eb12 Mon Sep 17 00:00:00 2001 From: Colin Watson Date: Sun, 9 Feb 2014 16:10:13 +0000 Subject: Document consequences of ssh-agent being setgid in ssh-agent(1) Bug-Debian: http://bugs.debian.org/711623 Forwarded: no Last-Update: 2013-06-08 Patch-Name: ssh-agent-setgid.patch --- ssh-agent.1 | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/ssh-agent.1 b/ssh-agent.1 index 83b2b41c8..7230704a3 100644 --- a/ssh-agent.1 +++ b/ssh-agent.1 @@ -206,6 +206,21 @@ environment variable holds the agent's process ID. .Pp The agent exits automatically when the command given on the command line terminates. +.Pp +In Debian, +.Nm +is installed with the set-group-id bit set, to prevent +.Xr ptrace 2 +attacks retrieving private key material. +This has the side-effect of causing the run-time linker to remove certain +environment variables which might have security implications for set-id +programs, including +.Ev LD_PRELOAD , +.Ev LD_LIBRARY_PATH , +and +.Ev TMPDIR . +If you need to set any of these environment variables, you will need to do +so in the program executed by ssh-agent. .Sh FILES .Bl -tag -width Ds .It Pa $TMPDIR/ssh-XXXXXXXXXX/agent.