EulerOS Virtualization 3.0.2.2 : dnsmasq (EulerOS-SA-2021-2134)

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

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

if (description)
{
  script_id(151408);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/12/08");

  script_cve_id("CVE-2020-25684", "CVE-2020-25685", "CVE-2020-25686");
  script_xref(name:"CEA-ID", value:"CEA-2021-0003");

  script_name(english:"EulerOS Virtualization 3.0.2.2 : dnsmasq (EulerOS-SA-2021-2134)");

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

  - A flaw was found in dnsmasq before version 2.83. When
    getting a reply from a forwarded query, dnsmasq checks
    in the forward.c:reply_query() if the reply destination
    address/port is used by the pending forwarded queries.
    However, it does not use the address/port to retrieve
    the exact forwarded query, substantially reducing the
    number of attempts an attacker on the network would
    have to perform to forge a reply and get it accepted by
    dnsmasq. This issue contrasts with RFC5452, which
    specifies a query's attributes that all must be used to
    match a reply. This flaw allows an attacker to perform
    a DNS Cache Poisoning attack. If chained with
    CVE-2020-25685 or CVE-2020-25686, the attack complexity
    of a successful attack is reduced. The highest threat
    from this vulnerability is to data
    integrity.(CVE-2020-25684)

  - 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-2021-2134
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?52557cee");
  script_set_attribute(attribute:"solution", value:
"Update the affected dnsmasq packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/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:H/PR:N/UI:N/S:U/C:N/I:L/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-2020-25686");

  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:"2021/07/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/07/06");

  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:uvp:3.0.2.2");
  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/cpu", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "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");
uvp = get_kb_item("Host/EulerOS/uvp_version");
if (uvp != "3.0.2.2") audit(AUDIT_OS_NOT, "EulerOS Virtualization 3.0.2.2");
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-2.76-5.h7.eulerosv2r7",
        "dnsmasq-utils-2.76-5.h7.eulerosv2r7"];

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