EulerOS 2.0 SP3 : krb5 (EulerOS-SA-2019-2600)

2019-12-18T00:00:00
ID EULEROS_SA-2019-2600.NASL
Type nessus
Reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-04-02T00:00:00

Description

According to the version of the krb5 packages installed, the EulerOS installation on the remote host is affected by the following vulnerability :

  • A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. If an attacker can obtain a krbtgt ticket using an older encryption type (single-DES, triple-DES, or RC4), the attacker can crash the KDC by making an S4U2Self request.(CVE-2018-20217)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(132135);
  script_version("1.2");
  script_cvs_date("Date: 2019/12/20");

  script_cve_id(
    "CVE-2018-20217"
  );

  script_name(english:"EulerOS 2.0 SP3 : krb5 (EulerOS-SA-2019-2600)");
  script_summary(english:"Checks the rpm output for the updated package.");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"According to the version of the krb5 packages installed, the EulerOS
installation on the remote host is affected by the following
vulnerability :

  - A Reachable Assertion issue was discovered in the KDC
    in MIT Kerberos 5 (aka krb5) before 1.17. If an
    attacker can obtain a krbtgt ticket using an older
    encryption type (single-DES, triple-DES, or RC4), the
    attacker can crash the KDC by making an S4U2Self
    request.(CVE-2018-20217)

Note that Tenable Network Security has extracted the preceding
description block directly from the EulerOS security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2019-2600
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a4b9982f");
  script_set_attribute(attribute:"solution", value:
"Update the affected krb5 package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:S/C:N/I:N/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:H/PR:L/UI:N/S:U/C:N/I:N/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:"patch_publication_date", value:"2019/12/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/18");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-pkinit");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-server-ldap");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:krb5-workstation");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libkadm5");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Huawei Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/sp");
  script_exclude_keys("Host/EulerOS/uvp_version");

  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/EulerOS/release");
if (isnull(release) || release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS");
if (release !~ "^EulerOS release 2\.0(\D|$)") audit(AUDIT_OS_NOT, "EulerOS 2.0");

sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(3)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP3");

uvp = get_kb_item("Host/EulerOS/uvp_version");
if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP3", "EulerOS UVP " + uvp);

if (!get_kb_item("Host/EulerOS/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, "EulerOS", cpu);

flag = 0;

pkgs = ["krb5-devel-1.15.1-34.h2",
        "krb5-libs-1.15.1-34.h2",
        "krb5-pkinit-1.15.1-34.h2",
        "krb5-server-1.15.1-34.h2",
        "krb5-server-ldap-1.15.1-34.h2",
        "krb5-workstation-1.15.1-34.h2",
        "libkadm5-1.15.1-34.h2"];

foreach (pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"3", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "krb5");
}