Amazon Linux AMI : libxml2 (ALAS-2016-719)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2016-719.
#

include("compat.inc");

if (description)
{
  script_id(92221);
  script_version("2.4");
  script_cvs_date("Date: 2019/04/11 17:23:06");

  script_cve_id("CVE-2016-1762", "CVE-2016-1833", "CVE-2016-1834", "CVE-2016-1835", "CVE-2016-1836", "CVE-2016-1837", "CVE-2016-1838", "CVE-2016-1839", "CVE-2016-1840", "CVE-2016-3627", "CVE-2016-3705", "CVE-2016-4447", "CVE-2016-4448", "CVE-2016-4449");
  script_xref(name:"ALAS", value:"2016-719");

  script_name(english:"Amazon Linux AMI : libxml2 (ALAS-2016-719)");
  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:
"A heap-based buffer overflow flaw was found in the way libxml2 parsed
certain crafted XML input. A remote attacker could provide a specially
crafted XML file that, when opened in an application linked against
libxml2, would cause the application to crash or execute arbitrary
code with the permissions of the user running the application.
(CVE-2016-1834 , CVE-2016-1840)

Multiple denial of service flaws were found in libxml2. A remote
attacker could provide a specially crafted XML file that, when
processed by an application using libxml2, could cause that
application to crash. (CVE-2016-1762 , CVE-2016-1833 , CVE-2016-1835 ,
CVE-2016-1836 , CVE-2016-1837 , CVE-2016-1838 , CVE-2016-1839 ,
CVE-2016-3627 , CVE-2016-3705 , CVE-2016-4447 , CVE-2016-4448 ,
CVE-2016-4449)"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2016-719.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Run 'yum update libxml2' to update your system."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  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-python26");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libxml2-python27");
  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:"2016/07/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/15");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  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:"libxml2-2.9.1-6.3.49.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-debuginfo-2.9.1-6.3.49.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-devel-2.9.1-6.3.49.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-python26-2.9.1-6.3.49.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-python27-2.9.1-6.3.49.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"libxml2-static-2.9.1-6.3.49.amzn1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
  else security_hole(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-python26 / etc");
}