CVE-2004-1653
The MITRE CVE dictionary describes this issue as:
The default configuration for OpenSSH enables AllowTcpForwarding, which could allow remote authenticated users to perform a port bounce, when configured with an anonymous access program such as AnonCVS.
Find out more about CVE-2004-1653 from the MITRE CVE dictionary dictionary and NIST NVD.
Statement
Permitting TCP forwarding is the expected and known default configuration. If it is not desired, it can disabled using the AllowTcpForwarding option in the /etc/ssh/sshd_config configuration file. However, only disabling TCP forwarding does not improve security unless users are also denied shell access. For more information, see man sshd_config.
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