Linux Distros Unpatched Vulnerability : CVE-2021-3782

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

include('compat.inc');

if (description)
{
  script_id(224053);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/09/05");

  script_cve_id("CVE-2021-3782");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2021-3782");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - An internal reference count is held on the buffer pool, incremented every time a new buffer is created
    from the pool. The reference count is maintained as an int; on LP64 systems this can cause the reference
    count to overflow if the client creates a large number of wl_shm buffer objects, or if it can coerce the
    server to create a large number of external references to the buffer storage. With the reference count
    overflowing, a use-after-free can be constructed on the wl_shm_pool tracking structure, where values may
    be incremented or decremented; it may also be possible to construct a limited oracle to leak 4 bytes of
    server-side memory to the attacking client at a time. (CVE-2021-3782)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2021-3782");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2021-3782");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/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:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/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-2021-3782");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/09/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/03/05");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libwayland-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libwayland-cursor");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libwayland-egl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libwayland-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:wayland");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:wayland-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:wayland-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:wayland");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libwayland-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libwayland-cursor");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libwayland-egl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libwayland-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:wayland");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:wayland-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:wayland-doc");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("set_linux_os_id.nasl", "ssh_get_info2.nasl");
  script_require_keys("Host/OS/identifier", "Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched");
  script_require_ports("Host/OS/CentOS Linux-7", "Host/OS/Debian Linux-11", "Host/OS/Red Hat Enterprise Linux-7", "Host/OS/Red Hat Enterprise Linux-9");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/CentOS/rpm-list")) && empty_or_null(get_one_kb_item("Host/Debian/dpkg-l")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Debian Linux-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "libwayland-bin"},
          {"reference": "libwayland-client0"},
          {"reference": "libwayland-cursor0"},
          {"reference": "libwayland-dev"},
          {"reference": "libwayland-doc"},
          {"reference": "libwayland-egl-backend-dev"},
          {"reference": "libwayland-egl1"},
          {"reference": "libwayland-server0"}
        ]
      }
    ]
  },
  "CentOS Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "libwayland-client"},
          {"reference": "libwayland-cursor"},
          {"reference": "libwayland-egl"},
          {"reference": "libwayland-server"},
          {"reference": "wayland"},
          {"reference": "wayland-devel"},
          {"reference": "wayland-doc"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "libwayland-client"},
          {"reference": "libwayland-cursor"},
          {"reference": "libwayland-egl"},
          {"reference": "libwayland-server"},
          {"reference": "wayland"},
          {"reference": "wayland-devel"},
          {"reference": "wayland-doc"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "libwayland-client"},
          {"reference": "libwayland-cursor"},
          {"reference": "libwayland-egl"},
          {"reference": "libwayland-server"},
          {"reference": "wayland-devel"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');
var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_NOTE,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}