CentOS 6 / 7 : pam (CESA-2015:1640)

2015-08-19T00:00:00
ID CENTOS_RHSA-2015-1640.NASL
Type nessus
Reporter This script is Copyright (C) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2019-12-02T00:00:00

Description

An updated pam package that fixes one security issue is now available for Red Hat Enterprise Linux 6 and 7.

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

Pluggable Authentication Modules (PAM) provide a system whereby administrators can set up authentication policies without having to recompile programs to handle authentication.

It was discovered that the _unix_run_helper_binary() function of PAM

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2015:1640 and 
# CentOS Errata and Security Advisory 2015:1640 respectively.
#

include("compat.inc");

if (description)
{
  script_id(85516);
  script_version("2.9");
  script_cvs_date("Date: 2019/10/02 15:30:20");

  script_cve_id("CVE-2015-3238");
  script_xref(name:"RHSA", value:"2015:1640");

  script_name(english:"CentOS 6 / 7 : pam (CESA-2015:1640)");
  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 updated pam package that fixes one security issue is now available
for Red Hat Enterprise Linux 6 and 7.

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

Pluggable Authentication Modules (PAM) provide a system whereby
administrators can set up authentication policies without having to
recompile programs to handle authentication.

It was discovered that the _unix_run_helper_binary() function of PAM's
unix_pam module could write to a blocking pipe, possibly causing the
function to become unresponsive. An attacker able to supply large
passwords to the unix_pam module could use this flaw to enumerate
valid user accounts, or cause a denial of service on the system.
(CVE-2015-3238)

Red Hat would like to thank Sebastien Macke of Trustwave SpiderLabs
for reporting this issue.

All pam users are advised to upgrade to this updated package, which
contains a backported patch to correct this issue."
  );
  # https://lists.centos.org/pipermail/centos-announce/2015-August/021339.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?e6ce238f"
  );
  # https://lists.centos.org/pipermail/centos-announce/2015-August/021340.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?fd631315"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected pam packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L");
  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:pam");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:pam-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/08/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/08/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/08/19");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015-2019 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);
release = get_kb_item("Host/CentOS/release");
if (isnull(release) || "CentOS" >!< release) audit(AUDIT_OS_NOT, "CentOS");
os_ver = pregmatch(pattern: "CentOS(?: Linux)? release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "CentOS");
os_ver = os_ver[1];
if (! preg(pattern:"^(6|7)([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "CentOS 6.x / 7.x", "CentOS " + os_ver);

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-6", reference:"pam-1.1.1-20.el6_7.1")) flag++;
if (rpm_check(release:"CentOS-6", reference:"pam-devel-1.1.1-20.el6_7.1")) flag++;

if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"pam-1.1.8-12.el7_1.1")) flag++;
if (rpm_check(release:"CentOS-7", cpu:"x86_64", reference:"pam-devel-1.1.8-12.el7_1.1")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "pam / pam-devel");
}