EulerOS 2.0 SP15 : libxml2 (EulerOS-SA-2026-3991)

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

include('compat.inc');

if (description)
{
  script_id(363991);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/08");

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

  script_name(english:"EulerOS 2.0 SP15 : libxml2 (EulerOS-SA-2026-3991)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS host is missing a security update.");
  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._x000D_
    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._x000D_
    Successful exploitation may cause a crash or potentially allow arbitrary code execution in the context of
    the xmlcatalog process._x000D_
    _x000D_
    This issue has been fixed in the commit c2e233fc._x000D_
    _x000D_
    NOTE:_x000D_
    The maintainers of this project did not agree that this issue is a vulnerability and considered it a
    bug.(CVE-2026-11979)

Tenable has extracted the preceding description block directly from the EulerOS libxml2 security advisory.

Note that Nessus has not tested for this issue 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-2026-3991
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7d6bdaf4");
  script_set_attribute(attribute:"solution", value:
"Update the affected libxml2 packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/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:"cvss4_vector", value:"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:L/SC:L/SI:L/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-11979");

  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:"2026/06/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/08");

  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_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 SP15");

var sp = get_kb_item("Host/EulerOS/sp");
if (isnull(sp) || sp !~ "^(15)$") audit(AUDIT_OS_NOT, "EulerOS 2.0 SP15");

if (!empty_or_null(uvp)) audit(AUDIT_OS_NOT, "EulerOS 2.0 SP15", "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 ("aarch64" >!< cpu) audit(AUDIT_ARCH_NOT, "aarch64", cpu);

var flag = 0;

var pkgs = [
  "libxml2-2.11.9-1.h21510.16.eulerosv2r15",
  "libxml2-devel-2.11.9-1.h21510.16.eulerosv2r15",
  "libxml2-help-2.11.9-1.h21510.16.eulerosv2r15",
  "python3-libxml2-2.11.9-1.h21510.16.eulerosv2r15"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", sp:"15", 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, "libxml2");
}