Linux Distros Unpatched Vulnerability : CVE-2026-67306

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

include('compat.inc');

if (description)
{
  script_id(331625);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/02");

  script_cve_id("CVE-2026-67306");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-67306");

  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.

  - FreeRDP versions 3.28.0 and earlier contain an out-of-bounds read vulnerability in the RDP6 planar RLE
    bitmap decoder functions planar_decompress_plane_rle and planar_decompress_plane_rle_only in
    libfreerdp/codec/planar.c. Only the 1-byte control byte is bounds-checked; the subsequent 015 attacker-
    declared raw bytes are read without validating that the source buffer contains them. A malicious or
    compromised RDP server can send a truncated planar-encoded bitmap or surface update (reachable via both
    the Bitmap Update PDU and RDPGFX Surface Command paths) that causes the client to read past the end of the
    source buffer. The issue is fixed in FreeRDP 3.29.0. (CVE-2026-67306)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-67306");
  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:N/AC:L/Au:N/C:P/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-67306");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/02");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:freerdp2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:freerdp3");
  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) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Debian Linux-11", "Host/OS/Debian Linux-12", "Host/OS/Debian Linux-13");

  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/Debian/dpkg-l"))) 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": "freerdp2-dev"},
          {"reference": "freerdp2-shadow-x11"},
          {"reference": "freerdp2-wayland"},
          {"reference": "freerdp2-x11"},
          {"reference": "libfreerdp-client2-2"},
          {"reference": "libfreerdp-server2-2"},
          {"reference": "libfreerdp-shadow-subsystem2-2"},
          {"reference": "libfreerdp-shadow2-2"},
          {"reference": "libfreerdp2-2"},
          {"reference": "libuwac0-0"},
          {"reference": "libuwac0-dev"},
          {"reference": "libwinpr-tools2-2"},
          {"reference": "libwinpr2-2"},
          {"reference": "libwinpr2-dev"},
          {"reference": "winpr-utils"}
        ]
      }
    ]
  },
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "freerdp2-dev"},
          {"reference": "freerdp2-shadow-x11"},
          {"reference": "freerdp2-wayland"},
          {"reference": "freerdp2-x11"},
          {"reference": "libfreerdp-client2-2"},
          {"reference": "libfreerdp-server2-2"},
          {"reference": "libfreerdp-shadow-subsystem2-2"},
          {"reference": "libfreerdp-shadow2-2"},
          {"reference": "libfreerdp2-2"},
          {"reference": "libuwac0-0"},
          {"reference": "libuwac0-dev"},
          {"reference": "libwinpr-tools2-2"},
          {"reference": "libwinpr2-2"},
          {"reference": "libwinpr2-dev"},
          {"reference": "winpr-utils"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "freerdp3-dev"},
          {"reference": "freerdp3-proxy"},
          {"reference": "freerdp3-proxy-modules"},
          {"reference": "freerdp3-sdl"},
          {"reference": "freerdp3-shadow-x11"},
          {"reference": "freerdp3-wayland"},
          {"reference": "freerdp3-x11"},
          {"reference": "libfreerdp-client3-3"},
          {"reference": "libfreerdp-server-proxy3-3"},
          {"reference": "libfreerdp-server3-3"},
          {"reference": "libfreerdp-shadow-subsystem3-3"},
          {"reference": "libfreerdp-shadow3-3"},
          {"reference": "libfreerdp3-3"},
          {"reference": "libwinpr-tools3-3"},
          {"reference": "libwinpr3-3"},
          {"reference": "libwinpr3-dev"},
          {"reference": "winpr3-utils"}
        ]
      }
    ]
  }
};

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 third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

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_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}