EulerOS 2.0 SP2 : unbound (EulerOS-SA-2021-2436)

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

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

if (description)
{
  script_id(153267);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/09/16");

  script_cve_id(
    "CVE-2019-25031",
    "CVE-2019-25032",
    "CVE-2019-25033",
    "CVE-2019-25034",
    "CVE-2019-25035",
    "CVE-2019-25036",
    "CVE-2019-25037",
    "CVE-2019-25038",
    "CVE-2019-25039",
    "CVE-2019-25040",
    "CVE-2019-25041",
    "CVE-2019-25042",
    "CVE-2020-28935"
  );

  script_name(english:"EulerOS 2.0 SP2 : unbound (EulerOS-SA-2021-2436)");
  script_summary(english:"Checks the rpm output for the updated packages.");

  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 unbound packages installed, the
EulerOS installation on the remote host is affected by the following
vulnerabilities :

  - NLnet Labs Unbound, up to and including version 1.12.0,
    and NLnet Labs NSD, up to and including version 4.3.3,
    contain a local vulnerability that would allow for a
    local symlink attack. When writing the PID file,
    Unbound and NSD create the file if it is not there, or
    open an existing file for writing. In case the file was
    already present, they would follow symlinks if the file
    happened to be a symlink instead of a regular file. An
    additional chown of the file would then take place
    after it was written, making the user Unbound/NSD is
    supposed to run as the new owner of the file. If an
    attacker has local access to the user Unbound/NSD runs
    as, she could create a symlink in place of the PID file
    pointing to a file that she would like to erase. If
    then Unbound/NSD is killed and the PID file is not
    cleared, upon restarting with root privileges,
    Unbound/NSD will rewrite any file pointed at by the
    symlink. This is a local vulnerability that could
    create a Denial of Service of the system Unbound/NSD is
    running on. It requires an attacker having access to
    the limited permission user Unbound/NSD runs as and
    point through the symlink to a critical file on the
    system.(CVE-2020-28935)

  - Unbound before 1.9.5 allows an assertion failure via a
    compressed name in dname_pkt_copy.(CVE-2019-25041)

  - Unbound before 1.9.5 allows an integer overflow in the
    regional allocator via the ALIGN_UP
    macro.(CVE-2019-25033)

  - Unbound before 1.9.5 allows an integer overflow in
    sldns_str2wire_dname_buf_origin, leading to an
    out-of-bounds write.(CVE-2019-25034)

  - Unbound before 1.9.5 allows an out-of-bounds write in
    sldns_bget_token_par.(CVE-2019-25035)

  - Unbound before 1.9.5 allows an infinite loop via a
    compressed name in dname_pkt_copy.(CVE-2019-25040)

  - Unbound before 1.9.5 allows an integer overflow in a
    size calculation in respip/respip.c.(CVE-2019-25039)

  - Unbound before 1.9.5 allows an assertion failure and
    denial of service in synth_cname.(CVE-2019-25036)

  - Unbound before 1.9.5 allows an integer overflow in a
    size calculation in
    dnscrypt/dnscrypt.c.(CVE-2019-25038)

  - Unbound before 1.9.5 allows an out-of-bounds write via
    a compressed name in rdata_copy.(CVE-2019-25042)

  - Unbound before 1.9.5 allows an assertion failure and
    denial of service in dname_pkt_copy via an invalid
    packet.(CVE-2019-25037)

  - Unbound before 1.9.5 allows configuration injection in
    create_unbound_ad_servers.sh upon a successful
    man-in-the-middle attack against a cleartext HTTP
    session.(CVE-2019-25031)

  - Unbound before 1.9.5 allows an integer overflow in the
    regional allocator via regional_alloc.(CVE-2019-25032)

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-2021-2436
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cd88756a");
  script_set_attribute(attribute:"solution", value:
"Update the affected unbound packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/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:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2019-25042");
  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:"2021/09/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/09/14");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:unbound");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:unbound-libs");
  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 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 !~ "^(2)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP2");

uvp = get_kb_item("Host/EulerOS/uvp_version");
if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP2", "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 = ["unbound-1.6.6-1.h5",
        "unbound-libs-1.6.6-1.h5"];

foreach (pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"2", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    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, "unbound");
}