Synology DiskStation Manager Out-of-bounds Write (CVE-2021-31439)

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

include('compat.inc');

if (description)
{
  script_id(502422);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/10/02");

  script_cve_id("CVE-2021-31439");

  script_name(english:"Synology DiskStation Manager Out-of-bounds Write (CVE-2021-31439)");

  script_set_attribute(attribute:"synopsis", value:
"The remote OT asset is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"This vulnerability allows network-adjacent attackers to execute
arbitrary code on affected installations of Synology DiskStation
Manager. Authentication is not required to exploit this vulnerablity.
The specific flaw exists within the processing of DSI structures in
Netatalk. The issue results from the lack of proper validation of the
length of user-supplied data prior to copying it to a heap-based
buffer. An attacker can leverage this vulnerability to execute code in
the context of the current process. Was ZDI-CAN-12326.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.");
  script_set_attribute(attribute:"see_also", value:"https://lists.debian.org/debian-lts-announce/2023/05/msg00018.html");
  script_set_attribute(attribute:"see_also", value:"https://security.gentoo.org/glsa/202311-02");
  script_set_attribute(attribute:"see_also", value:"https://www.debian.org/security/2023/dsa-5503");
  script_set_attribute(attribute:"see_also", value:"https://www.synology.com/zh-hk/security/advisory/Synology_SA_20_26");
  script_set_attribute(attribute:"see_also", value:"https://www.zerodayinitiative.com/advisories/ZDI-21-492/");
  script_set_attribute(attribute:"solution", value:
"Refer to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:A/AC:L/PR:N/UI:N/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:"cvss_score_source", value:"CVE-2021-31439");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(122, 787);

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/05/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/05/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/10/01");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:synology:diskstation_manager");
  script_set_attribute(attribute:"generated_plugin", value:"former");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Tenable.ot");

  script_copyright(english:"This script is Copyright (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("tenable_ot_api_integration.nasl");
  script_require_keys("Tenable.ot/Synology");

  exit(0);
}


include('tenable_ot_cve_funcs.inc');

get_kb_item_or_exit('Tenable.ot/Synology');

var asset = tenable_ot::assets::get(vendor:'Synology');

var vuln_cpes = {
    "cpe:/a:synology:diskstation_manager" :
        {"versionEndExcluding" : "6.2.3-25426-3", "versionStartIncluding" : "6.2", "family" : "DiskStation"}
};

tenable_ot::cve::compare_and_report(asset:asset, cpes:vuln_cpes, severity:SECURITY_WARNING);