Scientific Linux Security Update : sudo on SL6.x i386/x86_64 (20131121)

medium Nessus Plugin ID 71300
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Synopsis

The remote Scientific Linux host is missing one or more security updates.

Description

A flaw was found in the way sudo handled time stamp files. An attacker able to run code as a local user and with the ability to control the system clock could possibly gain additional privileges by running commands that the victim user was allowed to run via sudo, without knowing the victim's password. (CVE-2013-1775)

It was found that sudo did not properly validate the controlling terminal device when the tty_tickets option was enabled in the /etc/sudoers file. An attacker able to run code as a local user could possibly gain additional privileges by running commands that the victim user was allowed to run via sudo, without knowing the victim's password. (CVE-2013-2776, CVE-2013-2777)

This update also fixes the following bugs :

- Previously, sudo did not support netgroup filtering for sources from the System Security Services Daemon (SSSD).
Consequently, SSSD rules were applied to all users even when they did not belong to the specified netgroup. With this update, netgroup filtering for SSSD sources has been implemented. As a result, rules with a netgroup specification are applied only to users that are part of the netgroup.

- When the sudo utility set up the environment in which it ran a command, it reset the value of the RLIMIT_NPROC resource limit to the parent's value of this limit if both the soft (current) and hard (maximum) values of RLIMIT_NPROC were not limited. An upstream patch has been provided to address this bug and RLIMIT_NPROC can now be set to 'unlimited'.

- Due to the refactoring of the sudo code by upstream, the SUDO_USER variable that stores the name of the user running the sudo command was not logged to the /var/log/secure file as before. Consequently, user name 'root' was always recorded instead of the real user name. With this update, the previous behavior of sudo has been restored. As a result, the expected user name is now written to /var/log/secure.

- Due to an error in a loop condition in sudo's rule listing code, a buffer overflow could have occurred in certain cases. This condition has been fixed and the buffer overflow no longer occurs.

In addition, this update adds the following enhancements :

- With this update, sudo has been modified to send debug messages about netgroup matching to the debug log. These messages should provide better understanding of how sudo matches netgroup database records with values from the running system and what the values are exactly.

- With this update, sudo has been modified to accept the ipa_hostname value from the /etc/sssd/sssd.conf configuration file when matching netgroups.

Solution

Update the affected sudo, sudo-debuginfo and / or sudo-devel packages.

See Also

http://www.nessus.org/u?b44a6cac

Plugin Details

Severity: Medium

ID: 71300

File Name: sl_20131121_sudo_on_SL6_x.nasl

Version: 1.7

Type: local

Agent: unix

Published: 12/10/2013

Updated: 1/14/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Critical

Score: 9

CVSS v2

Risk Factor: Medium

Base Score: 6.9

Vector: AV:L/AC:M/Au:N/C:C/I:C/A:C

Vulnerability Information

CPE: p-cpe:/a:fermilab:scientific_linux:sudo, p-cpe:/a:fermilab:scientific_linux:sudo-debuginfo, p-cpe:/a:fermilab:scientific_linux:sudo-devel, x-cpe:/o:fermilab:scientific_linux

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/RedHat/release, Host/RedHat/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 11/21/2013

Vulnerability Publication Date: 3/5/2013

Exploitable With

CANVAS (CANVAS)

Metasploit (Mac OS X Sudo Password Bypass)

Reference Information

CVE: CVE-2013-1775, CVE-2013-2776, CVE-2013-2777