Ubuntu 4.10 : openssh information leakage (USN-34-1)

Medium Nessus Plugin ID 20650


The remote Ubuntu host is missing one or more security-related patches.


@Mediaservice.net discovered two information leaks in the OpenSSH server. When using password authentication, an attacker could test whether a login name exists by measuring the time between failed login attempts, i. e. the time after which the 'password:' prompt appears again.

A similar issue affects systems which do not allow root logins over ssh ('PermitRootLogin no'). By measuring the time between login attempts an attacker could check whether a given root password is correct. This allowed determining weak root passwords using a brute force attack.

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.


Update the affected packages.

Plugin Details

Severity: Medium

ID: 20650

File Name: ubuntu_USN-34-1.nasl

Version: $Revision: 1.12 $

Type: local

Agent: unix

Published: 2006/01/15

Modified: 2016/05/25

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:openssh-client, p-cpe:/a:canonical:ubuntu_linux:openssh-server, p-cpe:/a:canonical:ubuntu_linux:ssh, p-cpe:/a:canonical:ubuntu_linux:ssh-askpass-gnome, cpe:/o:canonical:ubuntu_linux:4.10

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Patch Publication Date: 2004/11/30

Reference Information

CVE: CVE-2003-0190

USN: 34-1