EulerOS 2.0 SP3 : dnsmasq (EulerOS-SA-2021-1775)

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

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

if (description)
{
  script_id(149190);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/02");

  script_cve_id("CVE-2017-15107", "CVE-2020-25685", "CVE-2020-25686");
  script_xref(name:"CEA-ID", value:"CEA-2021-0003");

  script_name(english:"EulerOS 2.0 SP3 : dnsmasq (EulerOS-SA-2021-1775)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"According to the versions of the dnsmasq packages installed, the
EulerOS installation on the remote host is affected by the following
vulnerabilities :

  - A vulnerability was found in the implementation of
    DNSSEC in Dnsmasq up to and including 2.78. Wildcard
    synthesized NSEC records could be improperly
    interpreted to prove the non-existence of hostnames
    that actually exist.(CVE-2017-15107)

  - A flaw was found in dnsmasq before version 2.83. When
    getting a reply from a forwarded query, dnsmasq checks
    in forward.c:reply_query(), which is the forwarded
    query that matches the reply, by only using a weak hash
    of the query name. Due to the weak hash (CRC32 when
    dnsmasq is compiled without DNSSEC, SHA-1 when it is)
    this flaw allows an off-path attacker to find several
    different domains all having the same hash,
    substantially reducing the number of attempts they
    would have to perform to forge a reply and get it
    accepted by dnsmasq. This is in contrast with RFC5452,
    which specifies that the query name is one of the
    attributes of a query that must be used to match a
    reply. This flaw could be abused to perform a DNS Cache
    Poisoning attack. If chained with CVE-2020-25684 the
    attack complexity of a successful attack is reduced.
    The highest threat from this vulnerability is to data
    integrity.(CVE-2020-25685)

  - A flaw was found in dnsmasq before version 2.83. When
    receiving a query, dnsmasq does not check for an
    existing pending request for the same name and forwards
    a new request. By default, a maximum of 150 pending
    queries can be sent to upstream servers, so there can
    be at most 150 queries for the same name. This flaw
    allows an off-path attacker on the network to
    substantially reduce the number of attempts that it
    would have to perform to forge a reply and have it
    accepted by dnsmasq. This issue is mentioned in the
    'Birthday Attacks' section of RFC5452. If chained with
    CVE-2020-25684, the attack complexity of a successful
    attack is reduced. The highest threat from this
    vulnerability is to data integrity.(CVE-2020-25686)

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-2021-1775
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4be2b5e9");
  script_set_attribute(attribute:"solution", value:
"Update the affected dnsmasq packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  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:N/I:H/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-15107");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"patch_publication_date", value:"2021/04/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/04/30");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dnsmasq");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:dnsmasq-utils");
  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) 2021-2024 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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_ARCH_NOT, "i686 / x86_64", cpu);

flag = 0;

pkgs = ["dnsmasq-2.76-2.2.h4",
        "dnsmasq-utils-2.76-2.2.h4"];

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_WARNING,
    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, "dnsmasq");
}