CentOS 7 : sudo (CESA-2016:2593)

2016-11-28T00:00:00
ID CENTOS_RHSA-2016-2593.NASL
Type nessus
Reporter Tenable
Modified 2018-11-10T00:00:00

Description

An update for sudo is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Low. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link (s) in the References section.

The sudo packages contain the sudo utility which allows system administrators to provide certain users with the permission to execute privileged commands, which are used for system management purposes, without having to log in as root.

Security Fix(es) :

  • It was discovered that the default sudo configuration preserved the value of INPUTRC from the user's environment, which could lead to information disclosure. A local user with sudo access to a restricted program that uses readline could use this flaw to read content from specially formatted files with elevated privileges provided by sudo. (CVE-2016-7091)

Note: With this update, INPUTRC was removed from the env_keep list in /etc/ sudoers to avoid having sudo preserve the value of this variable when invoking privileged commands.

Red Hat would like to thank Grisha Levit for reporting this issue.

Additional Changes :

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.3 Release Notes linked from the References section.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2016:2593 and 
# CentOS Errata and Security Advisory 2016:2593 respectively.
#

include("compat.inc");

if (description)
{
  script_id(95339);
  script_version("3.5");
  script_cvs_date("Date: 2018/11/10 11:49:32");

  script_cve_id("CVE-2016-7091");
  script_xref(name:"RHSA", value:"2016:2593");

  script_name(english:"CentOS 7 : sudo (CESA-2016:2593)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote CentOS host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"An update for sudo is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security
impact of Low. A Common Vulnerability Scoring System (CVSS) base
score, which gives a detailed severity rating, is available for each
vulnerability from the CVE link (s) in the References section.

The sudo packages contain the sudo utility which allows system
administrators to provide certain users with the permission to execute
privileged commands, which are used for system management purposes,
without having to log in as root.

Security Fix(es) :

* It was discovered that the default sudo configuration preserved the
value of INPUTRC from the user's environment, which could lead to
information disclosure. A local user with sudo access to a restricted
program that uses readline could use this flaw to read content from
specially formatted files with elevated privileges provided by sudo.
(CVE-2016-7091)

Note: With this update, INPUTRC was removed from the env_keep list in
/etc/ sudoers to avoid having sudo preserve the value of this variable
when invoking privileged commands.

Red Hat would like to thank Grisha Levit for reporting this issue.

Additional Changes :

For detailed information on changes in this release, see the Red Hat
Enterprise Linux 7.3 Release Notes linked from the References section."
  );
  # https://lists.centos.org/pipermail/centos-cr-announce/2016-November/003522.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?9415807b"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected sudo packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:sudo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:sudo-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/11/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/11/28");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"CentOS Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/CentOS/release", "Host/CentOS/rpm-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/CentOS/release")) audit(AUDIT_OS_NOT, "CentOS");
if (!get_kb_item("Host/CentOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "CentOS", cpu);


flag = 0;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"sudo-1.8.6p7-20.el7")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"sudo-devel-1.8.6p7-20.el7")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");