Amazon Linux AMI : openssl (ALAS-2015-564)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2015-564.
#

include("compat.inc");

if (description)
{
  script_id(84647);
  script_version("1.7");
  script_cvs_date("Date: 2018/04/18 15:09:35");

  script_cve_id("CVE-2015-1793");
  script_xref(name:"ALAS", value:"2015-564");

  script_name(english:"Amazon Linux AMI : openssl (ALAS-2015-564)");
  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:
"During certificate verfification, OpenSSL (starting from version
1.0.1n and 1.0.2b) will attempt to find an alternative certificate
chain if the first attempt to build such a chain fails. An error in
the implementation of this logic can mean that an attacker could cause
certain checks on untrusted certificates to be bypassed, such as the
CA flag, enabling them to use a valid leaf certificate to act as a CA
and 'issue' an invalid certificate.

This issue will impact any application that verifies certificates
including SSL/TLS/DTLS clients and SSL/TLS/DTLS servers using client
authentication.

The only version of OpenSSL from the Amazon Linux AMI that is impacted
by this CVE is openssl-1.0.1k-10.86.amzn1, which was published as
ALAS-2015-550."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2015-550.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2015-564.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Run 'yum update openssl' to update your system. Note that you may need
to run 'yum clean all' first."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N");

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

  script_set_attribute(attribute:"patch_publication_date", value:"2015/07/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/07/13");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015-2018 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:"openssl-1.0.1k-10.87.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssl-debuginfo-1.0.1k-10.87.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssl-devel-1.0.1k-10.87.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssl-perl-1.0.1k-10.87.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssl-static-1.0.1k-10.87.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, "openssl / openssl-debuginfo / openssl-devel / openssl-perl / etc");
}