EulerOS Virtualization 2.12.0 : unbound (EulerOS-SA-2026-1524)

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

include('compat.inc');

if (description)
{
  script_id(302639);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/03/16");

  script_cve_id("CVE-2025-5994", "CVE-2025-11411");

  script_name(english:"EulerOS Virtualization 2.12.0 : unbound (EulerOS-SA-2026-1524)");

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

    NLnet Labs Unbound up to and including version 1.24.1 is vulnerable to possible domain hijack attacks.
    Promiscuous NS RRSets that complement positive DNS replies in the authority section can be used to trick
    resolvers to update their delegation information for the zone. Usually these RRSets are used to update the
    resolver's knowledge of the zone's name servers. A malicious actor can exploit the possible poisonous
    effect by injecting NS RRSets (and possibly their respective address records) in a reply. This could be
    done for example by trying to spoof a packet or fragmentation attacks. Unbound would then proceed to
    update the NS RRSet data it already has since the new data has enough trust for it, i.e., in-zone data for
    the delegation point. Unbound 1.24.1 includes a fix that scrubs unsolicited NS RRSets (and their
    respective address records) from replies mitigating the possible poison effect. Unbound 1.24.2 includes an
    additional fix that scrubs unsolicited NS RRSets (and their respective address records) from YXDOMAIN and
    non-referral nodata replies, further mitigating the possible poison effect.(CVE-2025-11411)

    A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching
    resolvers that support EDNS Client Subnet (ECS). Unbound is also vulnerable when compiled with ECS
    support, i.e., '--enable-subnet', AND configured to send ECS information along with queries to upstream
    name servers, i.e., at least one of the 'send-client-subnet', 'client-subnet-zone' or 'client-subnet-
    always-forward' options is used. Resolvers supporting ECS need to segregate outgoing queries to
    accommodate for different outgoing ECS information. This re-opens up resolvers to a birthday paradox
    attack (Rebirthday Attack) that tries to match the DNS transaction ID in order to cache non-ECS poisonous
    replies.(CVE-2025-5994)

Tenable has extracted the preceding description block directly from the EulerOS Virtualization unbound 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-2026-1524
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cefd8be5");
  script_set_attribute(attribute:"solution", value:
"Update the affected unbound packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:C/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:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_supplemental", value:"CVSS:4.0/R:U/V:C");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-5994");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2025/07/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/03/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:python3-unbound");
  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:uvp:2.12.0");
  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) 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/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 (uvp != "2.12.0") audit(AUDIT_OS_NOT, "EulerOS Virtualization 2.12.0");
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 = [
  "python3-unbound-1.13.2-7.h9.eulerosv2r12",
  "unbound-1.13.2-7.h9.eulerosv2r12",
  "unbound-libs-1.13.2-7.h9.eulerosv2r12"
];

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