OpenSSH >= 2.3.0 AllowTcpForwarding Port Bouncing

medium Nessus Plugin ID 17744


The remote SSH server may permit anonymous port bouncing.


According to its banner, the remote host is running OpenSSH, version 2.3.0 or later. Such versions of OpenSSH allow forwarding TCP connections. If the OpenSSH server is configured to allow anonymous connections (e.g. AnonCVS), remote, unauthenticated users could use the host as a proxy.


Disallow anonymous users, set AllowTcpForwarding to 'no', or use the Match directive to restrict anonymous users.

See Also

Plugin Details

Severity: Medium

ID: 17744

File Name: openssh_tcp_forwarding.nasl

Version: 1.4

Type: remote

Family: Misc.

Published: 12/1/2011

Updated: 11/15/2018

Risk Information


Risk Factor: Low

Score: 3.7


Risk Factor: Medium

Base Score: 6.4

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:N

Vulnerability Information

CPE: cpe:/a:openbsd:openssh

Vulnerability Publication Date: 8/21/2004

Reference Information

CVE: CVE-2004-1653