EulerOS 2.0 SP11 : libxml2 (EulerOS-SA-2026-4252)

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

include('compat.inc');

if (description)
{
  script_id(364988);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/12");

  script_cve_id("CVE-2025-8732", "CVE-2026-6653", "CVE-2026-11979");
  script_xref(name:"IAVA", value:"2025-A-0840-S");
  script_xref(name:"IAVA", value:"2026-A-0532-S");

  script_name(english:"EulerOS 2.0 SP11 : libxml2 (EulerOS-SA-2026-4252)");

  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 libxml2 packages installed, the EulerOS installation on the remote host is affected by
the following vulnerabilities :

    libxml2 is vulnerable to multiple stack-based buffer overflows in the xmlcatalog utility when running in
    --shell mode. The usershell() function processes user input using fixed-size stack buffers without proper
    bounds checking.
    By supplying an overly long input line, an attacker can overflow internal buffers (command, arg, and argv)
    during input parsing. This results in memory corruption within the stack frame.
    Successful exploitation may cause a crash or potentially allow arbitrary code execution in the context of
    the xmlcatalog process.

    This issue has been fixed in the commit c2e233fc.

    NOTE:
    The maintainers of this project did not agree that this issue is a vulnerability and considered it a
    bug.(CVE-2026-11979)

    Use After Free in libxml2's xmlParseInternalSubset from GNOME libxml2 version 2.9.11 to 2.11.0 allows a
    remote attacker to cause a denial-of-service via maliciously crafted XML input with improper entity
    resolution handling.(CVE-2026-6653)

    A vulnerability was found in libxml2 up to 2.14.5. It has been declared as problematic. This vulnerability
    affects the function xmlParseSGMLCatalog of the component xmlcatalog. The manipulation leads to
    uncontrolled recursion. Attacking locally is a requirement. The exploit has been disclosed to the public
    and may be used. The real existence of this vulnerability is still doubted at the moment. The code
    maintainer explains, that '[t]he issue can only be triggered with untrusted SGML catalogs and it makes
    absolutely no sense to use untrusted catalogs. I also doubt that anyone is still using SGML catalogs at
    all.'(CVE-2025-8732)

Tenable has extracted the preceding description block directly from the EulerOS libxml2 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-2026-4252
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?0aef686f");
  script_set_attribute(attribute:"solution", value:
"Update the affected libxml2 packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:P");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-8732");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2026-6653");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-6653");

  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:"2025/08/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/12");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libxml2-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libxml2-help");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:python3-libxml2");
  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_info2.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 SP11");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(11)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP11");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP11", "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 = [
  "libxml2-2.9.12-5.h43.eulerosv2r11",
  "libxml2-devel-2.9.12-5.h43.eulerosv2r11",
  "libxml2-help-2.9.12-5.h43.eulerosv2r11",
  "python3-libxml2-2.9.12-5.h43.eulerosv2r11"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"11", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    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, "libxml2");
}