Oracle Linux 7 : krb5 (ELSA-2018-3071)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2018:3071 and 
# Oracle Linux Security Advisory ELSA-2018-3071 respectively.
#

include("compat.inc");

if (description)
{
  script_id(118768);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/04/14");

  script_cve_id("CVE-2018-5729", "CVE-2018-5730");
  script_xref(name:"RHSA", value:"2018:3071");

  script_name(english:"Oracle Linux 7 : krb5 (ELSA-2018-3071)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis",
    value:"The remote Oracle Linux host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description",
    value:
"From Red Hat Security Advisory 2018:3071 :

An update for krb5 is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security
impact of Low. 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.

Kerberos is a network authentication system, which can improve the
security of your network by eliminating the insecure practice of
sending passwords over the network in unencrypted form. It allows
clients and servers to authenticate to each other with the help of a
trusted third party, the Kerberos key distribution center (KDC).

Security Fix(es) :

* krb5: null dereference in kadmind or DN container check bypass by
supplying special crafted data (CVE-2018-5729)

* krb5: DN container check bypass by supplying special crafted data
(CVE-2018-5730)

For more details about the security issue(s), including the impact, a
CVSS score, and other related information, refer to the CVE page(s)
listed in the References section.

Additional Changes :

For detailed information on changes in this release, see the Red Hat
Enterprise Linux 7.6 Release Notes linked from the References section."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://oss.oracle.com/pipermail/el-errata/2018-November/008189.html"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected krb5 packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/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:H/UI:N/S:U/C:L/I:L/A:L");
  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:oracle:linux:krb5-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:krb5-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:krb5-pkinit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:krb5-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:krb5-server-ldap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:krb5-workstation");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:libkadm5");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:7");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/03/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/11/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/11/07");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Oracle Linux Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/OracleLinux", "Host/RedHat/release", "Host/RedHat/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);
if (!get_kb_item("Host/OracleLinux")) audit(AUDIT_OS_NOT, "Oracle Linux");
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || !pregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux)", string:release)) audit(AUDIT_OS_NOT, "Oracle Linux");
os_ver = pregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux) .*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Oracle Linux");
os_ver = os_ver[1];
if (! preg(pattern:"^7([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Oracle Linux 7", "Oracle Linux " + 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Oracle Linux", cpu);
if ("x86_64" >!< cpu) audit(AUDIT_ARCH_NOT, "x86_64", cpu);

flag = 0;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-devel-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-libs-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-pkinit-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-server-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-server-ldap-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"krb5-workstation-1.15.1-34.el7")) flag++;
if (rpm_check(release:"EL7", cpu:"x86_64", reference:"libkadm5-1.15.1-34.el7")) 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, "krb5-devel / krb5-libs / krb5-pkinit / krb5-server / etc");
}