CVE-2004-1653

published 2004-08-31

CVE-2004-1653: The default configuration for OpenSSH enables AllowTcpForwarding, which could allow remote authenticated users to perform a port bounce, when configured with…

Priority P2 71 medium 6.4 CVSS 2.0

AV N AC L Au N C P I P A N

ITW VulnCheck KEV

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
debian	openssh	—	—
openbsd	openssh	<= 3.9	—

Detection & IOCs extracted from sources · hover to see the quote

• → Look for OpenSSH configurations where AllowTcpForwarding is enabled (default) combined with anonymous access programs such as AnonCVS, which enables port bounce attacks by remote authenticated users. ↗

• · AllowTcpForwarding is enabled by default in OpenSSH. It can be disabled via the /etc/ssh/sshd_config configuration file, but disabling TCP forwarding alone does not improve security unless users are also denied shell access. ↗
• · The relevant configuration file to audit and harden is /etc/ssh/sshd_config for the AllowTcpForwarding directive. ↗

CVSS provenance

nvd v2.0 6.4 MEDIUM AV:N/AC:L/Au:N/C:P/I:P/A:N

vulncheck 6.4 MEDIUM

vendor_debian 6.4 LOW

vendor_redhat 6.4 MEDIUM

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