Amazon Linux AMI : libxml2 (ALAS-2013-188)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2013-188.
#

include("compat.inc");

if (description)
{
  script_id(69747);
  script_version("1.8");
  script_cvs_date("Date: 2018/04/18 15:09:35");

  script_cve_id("CVE-2013-0338");
  script_xref(name:"ALAS", value:"2013-188");

  script_name(english:"Amazon Linux AMI : libxml2 (ALAS-2013-188)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Amazon Linux AMI host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"libxml2 2.9.0 and earlier allows context-dependent attackers to cause
a denial of service (CPU and memory consumption) via an XML file
containing an entity declaration with long replacement text and many
references to this entity, aka 'internal entity expansion' with linear
complexity."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2013-188.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Run 'yum update libxml2' to update your system."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2-python");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2-static");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2013/05/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2013/09/04");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2013-2018 Tenable Network Security, Inc.");
  script_family(english:"Amazon Linux Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/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/AmazonLinux/release");
if (isnull(release) || !strlen(release)) audit(AUDIT_OS_NOT, "Amazon Linux");
os_ver = pregmatch(pattern: "^AL(A|\d)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "A")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux AMI", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (rpm_check(release:"ALA", reference:"libxml2-2.7.8-10.26.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-debuginfo-2.7.8-10.26.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-devel-2.7.8-10.26.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-python-2.7.8-10.26.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-static-2.7.8-10.26.amzn1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libxml2 / libxml2-debuginfo / libxml2-devel / libxml2-python / etc");
}