Scientific Linux: CVE-2012-0862 Low: xinetd Remote Access Issue

Date: Thu, 28 Feb 2013 16:16:42 -0600
Reply-To: Pat Riehecky 
Sender: Security Errata for Scientific Linux
 
From: Pat Riehecky 
Organization: Fermilab
Subject: Security ERRATA Low: xinetd on SL6.x i386/x86_64
MIME-Version: 1.0

Synopsis: Low: xinetd security and bug fix update
Issue Date: 2013-02-21
CVE Numbers: CVE-2012-0862
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When xinetd services are configured with the "TCPMUX" or "TCPMUXPLUS"
type, and the tcpmux-server service is enabled, those services are accessible via
port 1. It was found that enabling the tcpmux-server service (it is disabled by
default) allowed every xinetd service, including those that are not
configured with the "TCPMUX" or "TCPMUXPLUS" type, to be accessible via port 1.
This could allow a remote attacker to bypass intended firewall restrictions.
(CVE-2012-0862)

This update also fixes the following bugs:

* Prior to this update, a file descriptor array in the service.c source file
was not handled as expected. As a consequence, some of the descriptors
remained open when xinetd was under heavy load. Additionally, the system log was
filled with a large number of messages that took up a lot of disk space over time.
This update modifies the xinetd code to handle the file descriptors
correctly and messages no longer fill the system log.

* Prior to this update, services were disabled permanently when their
CPS limit was reached. As a consequence, a failed bind operation could occur when
xinetd attempted to restart the service. This update adds additional logic that
attempts to restart the service. Now, the service is only disabled if xinetd
cannot restart the service after 30 attempts.
--

SL6
 x86_64
 xinetd-2.3.14-38.el6.x86_64.rpm
 xinetd-debuginfo-2.3.14-38.el6.x86_64.rpm
 i386
 xinetd-2.3.14-38.el6.i686.rpm
 xinetd-debuginfo-2.3.14-38.el6.i686.rpm

- Scientific Linux Development Team