EulerOS 2.0 SP8 : dhcp (EulerOS-SA-2021-2291)

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(152282);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/12/06");

  script_cve_id("CVE-2021-25217");

  script_name(english:"EulerOS 2.0 SP8 : dhcp (EulerOS-SA-2021-2291)");

  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 dhcp packages installed, the EulerOS
installation on the remote host is affected by the following
vulnerability :

  - In ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16, ISC DHCP 4.4.0
    -> 4.4.2 (Other branches of ISC DHCP (i.e., releases in
    the 4.0.x series or lower and releases in the 4.3.x
    series) are beyond their End-of-Life (EOL) and no
    longer supported by ISC. From inspection it is clear
    that the defect is also present in releases from those
    series, but they have not been officially tested for
    the vulnerability), The outcome of encountering the
    defect while reading a lease that will trigger it
    varies, according to: the component being affected
    (i.e., dhclient or dhcpd) whether the package was built
    as a 32-bit or 64-bit binary whether the compiler flag
    -fstack-protection-strong was used when compiling In
    dhclient, ISC has not successfully reproduced the error
    on a 64-bit system. However, on a 32-bit system it is
    possible to cause dhclient to crash when reading an
    improper lease, which could cause network connectivity
    problems for an affected system due to the absence of a
    running DHCP client process. In dhcpd, when run in
    DHCPv4 or DHCPv6 mode: if the dhcpd server binary was
    built for a 32-bit architecture AND the
    -fstack-protection-strong flag was specified to the
    compiler, dhcpd may exit while parsing a lease file
    containing an objectionable lease, resulting in lack of
    service to clients. Additionally, the offending lease
    and the lease immediately following it in the lease
    database may be improperly deleted. if the dhcpd server
    binary was built for a 64-bit architecture OR if the
    -fstack-protection-strong compiler flag was NOT
    specified, the crash will not occur, but it is possible
    for the offending lease and the lease which immediately
    followed it to be improperly deleted.(CVE-2021-25217)

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-2021-2291
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?96402a9d");
  script_set_attribute(attribute:"solution", value:
"Update the affected dhcp package.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-25217");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"patch_publication_date", value:"2021/08/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/08/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dhcp-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dhcp-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dhcp-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dhcp-relay");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dhcp-server");
  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) 2021-2023 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 !~ "^(8)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP8");

uvp = get_kb_item("Host/EulerOS/uvp_version");
if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP8", "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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("aarch64" >!< cpu) audit(AUDIT_ARCH_NOT, "aarch64", cpu);

flag = 0;

pkgs = ["dhcp-client-4.3.6-28.h17.eulerosv2r8",
        "dhcp-common-4.3.6-28.h17.eulerosv2r8",
        "dhcp-libs-4.3.6-28.h17.eulerosv2r8",
        "dhcp-relay-4.3.6-28.h17.eulerosv2r8",
        "dhcp-server-4.3.6-28.h17.eulerosv2r8"];

foreach (pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"8", 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, "dhcp");
}