[Bug 3700] New: Unresponsive domain names freeze SSH connection when using SOCKS proxy

[bugzilla-daemon at mindrot.org]

https://bugzilla.mindrot.org/show_bug.cgi?id=3700

            Bug ID: 3700
           Summary: Unresponsive domain names freeze SSH connection when
                    using SOCKS proxy
           Product: Portable OpenSSH
           Version: 9.1p1
          Hardware: amd64
                OS: Linux
            Status: NEW
          Severity: critical
          Priority: P5
         Component: sshd
          Assignee: unassigned-bugs at mindrot.org
          Reporter: timothy_holt123 at yahoo.co.uk

I enable dynamic port forwarding and set browser to SOCKS proxy with
remote DNS lookup on.

The whole SSH connection freezes when going on ebay.co.uk in my browser
(Firefox) with "open failed: connect failed: Try again" printed several
times in the terminal and the only way to get it working again is to
kill the ssh process and restart it. I narrowed it down to
ebay.entmag.co.uk causing the freeze and get "Temporary failure in name
resolution" when pinging it.

Going on ebay.entmag.co.uk directly in the browser through the SOCKS
proxy causes connection to freeze up for around a minute until the
browser errors out.

This is a serious bug and makes dynamic port forwarding vulnerable to
DDoS attacks.

-- 
You are receiving this mail because:
You are watching the assignee of the bug.