RHEL 6 : gnutls (RHSA-2017:0574)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2017:0574. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(97874);
  script_version("3.11");
  script_cvs_date("Date: 2019/10/24 15:35:42");

  script_cve_id("CVE-2016-8610", "CVE-2017-5335", "CVE-2017-5336", "CVE-2017-5337");
  script_xref(name:"RHSA", value:"2017:0574");

  script_name(english:"RHEL 6 : gnutls (RHSA-2017:0574)");
  script_summary(english:"Checks the rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Red Hat host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"An update for gnutls is now available for Red Hat Enterprise Linux 6.

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

The gnutls packages provide the GNU Transport Layer Security (GnuTLS)
library, which implements cryptographic algorithms and protocols such
as SSL, TLS, and DTLS.

The following packages have been upgraded to a later upstream version:
gnutls (2.12.23). (BZ#1321112, BZ#1326073, BZ#1415682, BZ#1326389)

Security Fix(es) :

* A denial of service flaw was found in the way the TLS/SSL protocol
defined processing of ALERT packets during a connection handshake. A
remote attacker could use this flaw to make a TLS/SSL server consume
an excessive amount of CPU and fail to accept connections form other
clients. (CVE-2016-8610)

* Multiple flaws were found in the way gnutls processed OpenPGP
certificates. An attacker could create specially crafted OpenPGP
certificates which, when parsed by gnutls, would cause it to crash.
(CVE-2017-5335, CVE-2017-5336, CVE-2017-5337)

Additional Changes :

For detailed information on changes in this release, see the Red Hat
Enterprise Linux 6.9 Release Notes and Red Hat Enterprise Linux 6.9
Technical Notes linked from the References section."
  );
  # https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?b5caa05f"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2017:0574"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2016-8610"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2017-5335"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2017-5336"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2017-5337"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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:H/I:H/A:H");
  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:redhat:enterprise_linux:gnutls");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:gnutls-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:gnutls-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:gnutls-guile");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:gnutls-utils");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/03/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/03/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/22");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Red Hat Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Red Hat" >!< release) audit(AUDIT_OS_NOT, "Red Hat");
os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Red Hat");
os_ver = os_ver[1];
if (! preg(pattern:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 6.x", "Red Hat " + os_ver);

if (!get_kb_item("Host/RedHat/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$" && "s390" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2017:0574";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : yum_report 
    );
    exit(0);
  }
  else
  {
    audit_message = "affected by Red Hat security advisory " + rhsa;
    audit(AUDIT_OS_NOT, audit_message);
  }
}
else
{
  flag = 0;
  if (rpm_check(release:"RHEL6", reference:"gnutls-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", reference:"gnutls-debuginfo-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", reference:"gnutls-devel-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", reference:"gnutls-guile-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"gnutls-utils-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"gnutls-utils-2.12.23-21.el6")) flag++;
  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"gnutls-utils-2.12.23-21.el6")) flag++;

  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : rpm_report_get() + redhat_report_package_caveat()
    );
    exit(0);
  }
  else
  {
    tested = pkg_tests_get();
    if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
    else audit(AUDIT_PACKAGE_NOT_INSTALLED, "gnutls / gnutls-debuginfo / gnutls-devel / gnutls-guile / etc");
  }
}