EulerOS 2.0 SP12 : dnsmasq (EulerOS-SA-2026-2524)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(326193);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/10");

  script_cve_id("CVE-2026-4892", "CVE-2026-4893");
  script_xref(name:"IAVA", value:"2026-A-0450");

  script_name(english:"EulerOS 2.0 SP12 : dnsmasq (EulerOS-SA-2026-2524)");

  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 :

    An information disclosure vulnerability in dnsmasq allows remote attackers to bypass source checks via a
    crafted DNS packet with RFC 7871 client subnet information.(CVE-2026-4893)

    A heap-based out-of-bounds write vulnerability in the DHCPv6 implementation of dnsmasq allows local
    attackers to execute arbitrary code with root privileges via a crafted DHCPv6 packet.(CVE-2026-4892)

Tenable has extracted the preceding description block directly from the EulerOS dnsmasq security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2026-2524
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?89536264");
  script_set_attribute(attribute:"solution", value:
"Update the affected dnsmasq packages.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:L/Au:N/C:C/I:C/A:C");
  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:U/C:H/I:H/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-2026-4892");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/05/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/10");

  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-help");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:2.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2026 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/sp");
  script_exclude_keys("Host/EulerOS/uvp_version");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var _release = get_kb_item("Host/EulerOS/release");
if (isnull(_release) || _release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS");
var uvp = get_kb_item("Host/EulerOS/uvp_version");
if (_release !~ "^EulerOS release 2\.0(\D|$)") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP12");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(12)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP12");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP12", "EulerOS UVP " + uvp);

if (!get_kb_item("Host/EulerOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "aarch64" >!< cpu && "x86" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$" && "x86" >!< cpu) audit(AUDIT_ARCH_NOT, "i686 / x86_64", cpu);

var flag = 0;

var pkgs = [
  "dnsmasq-2.86-3.h16.eulerosv2r12",
  "dnsmasq-help-2.86-3.h16.eulerosv2r12"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"12", reference:pkg)) flag++;

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