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Vulnerability of Nagios Plugins: information disclosure via check_dhcp

Synthesis of the vulnerability 

An attacker can use check_dhcp of Nagios Plugins, to read a file with INI format, in order to obtain sensitive information.
Vulnerable software: Fedora, Nagios Open Source.
Severity of this announce: 2/4.
Creation date: 16/05/2014.
Références of this computer vulnerability: CVE-2014-4701, FEDORA-2015-12972, FEDORA-2015-12987, VIGILANCE-VUL-14761.

Description of the vulnerability 

The check_dhcp script of Nagios Plugins checks the availability of DHCP servers. This script is installed suid root:

The "--extra-opts" option is used to read a file in format INI :
  [section]
  var=val

However, check_dhcp reads these files with root privileges.

An attacker can therefore use check_dhcp of Nagios Plugins, to read a file with INI format, in order to obtain sensitive information.
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This security weakness impacts software or systems such as Fedora, Nagios Open Source.

Our Vigil@nce team determined that the severity of this threat bulletin is medium.

The trust level is of type confirmed by the editor, with an origin of user shell.

A proof of concept or an attack tool is available, so your teams have to process this alert. An attacker with a technician ability can exploit this threat.

Solutions for this threat 

Nagios Plugins: version 2.0.2.
The version 2.0.2 is fixed:
  http://nagios-plugins.org/downloads/

Nagios Plugins: workaround for check_dhcp.
A workaround is to remove the suid bit of check_dhcp:
  chmod -s /usr/local/nagios/libexec/check_dhcp

Fedora: new nagios-plugins packages.
New packages are available:
  Fedora 21: nagios-plugins 2.0.3-1.fc21
  Fedora 22: nagios-plugins 2.0.3-1.fc22
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