EulerOS Virtualization 2.12.0 : util-linux (EulerOS-SA-2026-2810)

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

include('compat.inc');

if (description)
{
  script_id(328630);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/21");

  script_cve_id("CVE-2026-27456");

  script_name(english:"EulerOS Virtualization 2.12.0 : util-linux (EulerOS-SA-2026-2810)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS Virtualization host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"According to the versions of the util-linux packages installed, the EulerOS Virtualization installation on the remote
host is affected by the following vulnerabilities :

    util-linux is a random collection of Linux utilities. Prior to version 2.41.4, a TOCTOU (Time-of-Check-
    Time-of-Use) vulnerability has been identified in the SUID binary /usr/bin/mount from util-linux. The
    mount binary, when setting up loop devices, validates the source file path with user privileges via fork()
    + setuid() + realpath(), but subsequently re-canonicalizes and opens it with root privileges (euid=0)
    without verifying that the path has not been replaced between both operations. Neither O_NOFOLLOW, nor
    inode comparison, nor post-open fstat() are employed. This allows a local unprivileged user to replace the
    source file with a symlink pointing to any root-owned file or device during the race window, causing the
    SUID binary to open and mount it as root. Exploitation requires an /etc/fstab entry with user,loop options
    whose path points to a directory where the attacker has write permission, and that /usr/bin/mount has the
    SUID bit set (the default configuration on virtually all Linux distributions). The impact is unauthorized
    read access to root-protected files and block devices, including backup images, disk volumes, and any file
    containing a valid filesystem. This issue has been patched in version 2.41.4.(CVE-2026-27456)

Tenable has extracted the preceding description block directly from the EulerOS Virtualization util-linux 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-2026-2810
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a6d886cb");
  script_set_attribute(attribute:"solution", value:
"Update the affected util-linux packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:H/Au:S/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-27456");

  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:"2026/04/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libblkid");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libfdisk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libmount");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libsmartcols");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:libuuid");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:util-linux");
  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 = [
  "libblkid-2.37.2-13.h33.eulerosv2r12",
  "libfdisk-2.37.2-13.h33.eulerosv2r12",
  "libmount-2.37.2-13.h33.eulerosv2r12",
  "libsmartcols-2.37.2-13.h33.eulerosv2r12",
  "libuuid-2.37.2-13.h33.eulerosv2r12",
  "util-linux-2.37.2-13.h33.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_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, "util-linux");
}