Amazon Linux AMI : openssh (ALAS-2015-568)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2015-568.
#

include("compat.inc");

if (description)
{
  script_id(84928);
  script_version("2.3");
  script_cvs_date("Date: 2018/04/18 15:09:35");

  script_cve_id("CVE-2015-5352");
  script_xref(name:"ALAS", value:"2015-568");

  script_name(english:"Amazon Linux AMI : openssh (ALAS-2015-568)");
  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:
"It was reported that when forwarding X11 connections with
ForwardX11Trusted=no, connections made after ForwardX11Timeout expired
could be permitted and no longer subject to XSECURITY restrictions
because of an ineffective timeout check in ssh(1) coupled with 'fail
open' behavior in the X11 server when clients attempted connections
with expired credentials."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2015-568.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Run 'yum update openssh' to update your system."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh-clients");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh-keycat");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh-ldap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:openssh-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:pam_ssh_agent_auth");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2015/07/22");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/07/23");
  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:"openssh-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssh-clients-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssh-debuginfo-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssh-keycat-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssh-ldap-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"openssh-server-6.2p2-8.44.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"pam_ssh_agent_auth-0.9.3-5.8.44.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, "openssh / openssh-clients / openssh-debuginfo / openssh-keycat / etc");
}