No memory limit for dom0less domUs (XSA-383) - Nessus

Medium Plugin ID: 159892

This page contains detailed information about the No memory limit for dom0less domUs (XSA-383) Nessus plugin including available exploits and PoCs found on GitHub, in Metasploit or Exploit-DB for verifying of this vulnerability.

Table Of Contents

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Plugin Overview
Vulnerability Information

Synopsis
Description
Solution

Public Exploits
Risk Information
Plugin Source
How to Run
References
Version

Plugin Overview

ID: 159892
Name: No memory limit for dom0less domUs (XSA-383)
Filename: xen_server_XSA-383.nasl
Vulnerability Published: 2021-08-25
This Plugin Published: 2022-04-19
Last Modification Time: 2022-04-27
Plugin Version: 1.3
Plugin Type: local
Plugin Family: Misc.
Dependencies: xen_server_detect.nbin
Required KB Items [?]: installed_sw/Xen Hypervisor, Settings/ParanoidReport

Vulnerability Information

Severity: Medium
Vulnerability Published: 2021-08-25
Patch Published: 2021-08-25
CVE [?]: CVE-2021-28700
CPE [?]: cpe:/o:xen:xen

Synopsis

The remote Xen hypervisor installation is missing a security update.

Description

The dom0less feature allows an administrator to create multiple unprivileged domains directly from Xen. Unfortunately, the memory limit from them is not set. This allows a domain to allocate memory beyond what an administrator originally configured.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Apply the appropriate patch according to the vendor advisory.

Public Exploits

Target Network Port(s): N/A
Target Asset(s): N/A
Exploit Available: True (GitHub)
Exploit Ease: Exploits (PoCs) are available

Here's the list of publicly known exploits and PoCs for verifying the No memory limit for dom0less domUs (XSA-383) vulnerability:

GitHub: https://github.com/AlAIAL90/CVE-2021-28700
[CVE-2021-28700: PoC for exploiting CVE-2021-28700 : xen/arm: No memory limit for dom0less domUs The ...]

Before running any exploit against any system, make sure you are authorized by the owner of the target system(s) to perform such activity. In any other case, this would be considered as an illegal activity.

WARNING: Beware of using unverified exploits from sources such as GitHub or Exploit-DB. These exploits and PoCs could contain malware. For more information, see how to use exploits safely.

Risk Information

CVSS Score Source [?]: CVE-2021-28700
CVSS V2 Vector: AV:N/AC:L/Au:S/C:N/I:N/A:C/E:U/RL:OF/RC:C

CVSS Base Score:	6.8 (Medium)
Impact Subscore:	6.9
Exploitability Subscore:	8.0
CVSS Temporal Score:	5.0 (Medium)
CVSS Environmental Score:	NA (None)
Modified Impact Subscore:	NA
Overall CVSS Score:	5.0 (Medium)

CVSS V3 Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

CVSS Base Score:	4.9 (Medium)
Impact Subscore:	3.6
Exploitability Subscore:	1.2
CVSS Temporal Score:	4.3 (Medium)
CVSS Environmental Score:	NA (None)
Modified Impact Subscore:	NA
Overall CVSS Score:	4.3 (Medium)

STIG Severity [?]: I
STIG Risk Rating: High

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Plugin Source

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(159892);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/04/27");

  script_cve_id("CVE-2021-28700");
  script_xref(name:"IAVB", value:"2021-B-0061-S");

  script_name(english:"No memory limit for dom0less domUs (XSA-383)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Xen hypervisor installation is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The dom0less feature allows an administrator to create multiple
unprivileged domains directly from Xen.  Unfortunately, the
memory limit from them is not set. This allows a domain to allocate
memory beyond what an administrator originally configured.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://xenbits.xen.org/xsa/advisory-383.html");
  script_set_attribute(attribute:"solution", value:
"Apply the appropriate patch according to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/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-2021-28700");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/08/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/08/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/04/19");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:xen:xen");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("xen_server_detect.nbin");
  script_require_keys("installed_sw/Xen Hypervisor", "Settings/ParanoidReport");

  exit(0);
}

include('vcf.inc');
include('vcf_extras.inc');

var fixes;
var app = 'Xen Hypervisor';
var app_info = vcf::xen_hypervisor::get_app_info(app:app);
if (report_paranoia < 2) audit(AUDIT_PARANOID);

fixes['4.12']['fixed_ver']           = '4.12.4';
fixes['4.12']['fixed_ver_display']   = '4.12.4 (changeset 35ba323)';
fixes['4.12']['affected_ver_regex']  = "^4\.12([^0-9]|$)";
fixes['4.12']['affected_changesets'] = make_list('9e39b7f', '090986b',
  'e8f95a6', '90ae827', '4e5bf7e', 'b2f52a0', '22bd06c', '52ee570', 
  '1f5c237', 'aac5e50', '724eebc', 'dd59be6', 'd446431', '05e64a6', 
  '2f4cfe5', '0475382', 'bd52c7e', '7dadebd', 'c6c5f9d', 'ea20eee', 
  '99f2c46', 'd024fe1', 'e5f3be9', 'e318c13', 'ced413b', '95d23c7', 
  'aa8866c', '2c39570', '5984905', '5b280a5', '955c604', 'cd5666c', 
  '1df73ab', 'b406997', 'f66542f', '26764c5', 'b100d3e', '17db0ba', 
  '2e9e9e4', '652a259', 'b8737d2', '70c53ea', '4cf5929', '8d26cdd', 
  'f1f3226', 'cce7cbd', '2525a74', 'c8b97ff', '2186c16', '51e9505', 
  '4943ea7', '3c13a87', 'd4b884b', '7da9325', 'd6d3b13', '9fe89e1', 
  'd009b8d', '674108e', 'bfda5ae', '551d75d', '5e1bac4', 'f8443e8', 
  '655190d', 'f860f42', '9f73020', 'aeebc0c', 'f1a4126', 'b1efedb', 
  '4739f79', '0dbcdcc', '444b717', '544a775', 'c64ff3b', '8145d38', 
  '14f577b', '40ab019', '1dd870e', '5c15a1c', '6602544', '14c9c0f', 
  'dee5d47', '7b2f479', '46ad884', 'eaafa72', '0e6975b', '8e0c2a2', 
  '51eca39', '7ae2afb', '5e11fd5', '34056b2', 'fd4cc0b', '4f9294d', '97b7b55');

fixes['4.13']['fixed_ver']           = '4.13.4';
fixes['4.13']['fixed_ver_display']   = '4.13.4-pre (changeset bdb8480)';
fixes['4.13']['affected_ver_regex']  = "^4\.13([^0-9]|$)";
fixes['4.13']['affected_changesets'] = make_list('985b3e5', '4d65fe9',
  '9d954c8', '53e797c', '89d40f0', 'f762403', 'ebeb9ec', '2357043', 
  '18fe877', '41200e0', '0ed0cdd', 'ecb4697', 'f50fbdd', '75bb9fe', 
  '4fa8b13', '85dc71b', '3cdc7b6', '32d5809', '41e8d5d', '27e08cb', 
  'f6f7690', '1f27fc4', 'a7de760', '1540a9a', '351c890', '3f3ebda', 
  '7907ab8', 'ddb3edb', 'e39050c', '235bfe8', '84bc28f', '9eece40', 
  '2c9da5f', '5aacd07', '64752a9', '948b7c8', '9bd6416', '97af34f', 
  'f799329', '0a3eb9b', 'd3d8a29', '83c0f6b', '9e3c8b1', 'def4352', 
  '95197d4', 'ef8b235', 'f17d848', 'fa5afbb', '4d54414', '287f229', 
  'e289ed6', '2841329', '33049e3', '53f4ce9', '8113b02', '0e711a0', 
  '21e1ae3', '4352a49', 'e93d278', '231237c', 'ca06bce', '5aef2c5', 
  '5de1558', 'e3bcd4d');

fixes['4.14']['fixed_ver']           = '4.14.3';
fixes['4.14']['fixed_ver_display']   = '4.14.3-pre (changeset c439f5e)';
fixes['4.14']['affected_ver_regex']  = "^4\.14([^0-9]|$)";
fixes['4.14']['affected_changesets'] = make_list('66f5e86', 'b81187f',
  '29aeeda', '98bcd53', '6f4c214', '9685265', 'e4c2384', '1958758', 
  'fe6da09', '4a24451', '100b2e2', '8da1491', 'f7a9730', '61f2806', 
  '49299c4', 'b46af13', 'e32e184', 'bb731fd', 'c3cc6e2', 'bb9377a', 
  'f6aec84', '23d5e3d', '3cfccd7', '1ed3661', '645fcf8', '86c223c', 
  '79774e0', 'e06d0c1', '1dae9fd', '64d93d6', '3ae25fc', '665024b', 
  'ecd6b17', 'c6ee6d4', 'b6a8c4f', '45710c0', 'ee5425c', '4b4ee05', 
  '768138c', '0ff7f9c', 'fcf98ef', '51278ce', '766b1f4', 'e5bce3a', 
  '46ff245', '2665d97', '7053c8e', '5caa690', 'b046e05', '3f85493', 
  'ac507e0', 'ebfdf0c', '9d963a7', 'b15c24a', 'f23cb47', 'c2f78b4', 'a351751');

fixes['4.15']['fixed_ver']           = '4.15.1';
fixes['4.15']['fixed_ver_display']   = '4.15.1-pre (changeset 9bc2a68)';
fixes['4.15']['affected_ver_regex']  = "^4\.15([^0-9]|$)";
fixes['4.15']['affected_changesets'] = make_list('8a8b16c', '2f6ebce',
  '9bfbde4', 'd40287a', '7850fe5', '9f44ed1', '27bc41d', 'd39756f', 
  '711aeb1', '34d141e', '29a6cf1', '92c8b92', '1beb196', '6bbdcef', 
  'abfbb29', 'c3cf33b', 'e0da171', 'c773053', '0f1002d', '00bd594', 
  '0e419e4', 'e3f5318', '4b60715', 'e949445', '9cb597a', '6165dcf', 
  'da659f6', '17dca16', '99633c5', '2b23bb6', 'dba7748', 'e98cacf', 
  '0e1407f', '61dea45', '429b0a5', '41f0903', '67f7989', 'e9709a8', 
  '1a68249', 'e6d098e', '16d2641', '7b658fd', '6ba107c', '2ba0d81', 
  '3581714', '0b80b34', 'd8a530e', '9892901', '3556dc6', '13ea8af', 
  '77069ea', 'ec457ac', '4586e64', '796d405', '0aabeb9', 'a339cea', 
  '874dac9', 'f034c96', '894636d', '12ebf0f', '35b5836', '8368f21', 
  '7044184', '0a64b18', 'eae0dfa', '89c6e84', '7c3c984', '6a7e21a', 
  'ee2b1d6', 'edeaa04', 'cacad0c', '3e6c1b6', '78a7c3b', '280d472', 
  'eb1f325', 'dfcce09', 'c129b5f', 'e2e80ff', '5788a7e', 'bb071ce', 
  '92dd3b5', 'baa6957', 'c86d8ec', 'e72bf72');

fixes['4.16']['fixed_ver']           = '4.16';
fixes['4.16']['fixed_ver_display']   = '4.16-unstable (changeset b75838a)';
fixes['4.16']['affected_ver_regex']  = "^4\.16([^0-9]|$)";
fixes['4.16']['affected_changesets'] = make_list('57f8785', '1e6706b',
  '2f5f0a1', '9516d01', '4cfab44', 'a0ffee6', '048de2c', '9e319e5', 
  'dbb9481', 'c8c6cd9', 'f929448', '3b38b1d', 'a1743fc', 'eb7518b', 
  '2faeb42', 'd3b05f9', '2d7f191', '834cb87', '036432e', 'e5ba9f7', 
  'aa44f3c', '71cf763', 'e26f810', 'bc2bdd4', '4817dbf', 'f38c859', 
  'e8b42a4', '2fac4e3', 'b6b672e', '24b0ce9', '664cc3c', 'd4c9845', 
  'e17abb2', '86e84e5', '8858dfa', '305f193', 'b11380f', '1d34553', 
  '2075b41', 'a095542', '1da6a07', '6ec9176', '15517ed', 'f9187cf', 
  '2a04f39', '74c48d4', '192aaf7', 'd6bdad3', 'efbd25c', '58ce57a', 
  '4b88b4b', 'b6fe410', '60649d4', '4eb1728', 'a9a34e2', 'c2f40d8', 
  'c9aa02e', '5d15f90', 'f01be29', '65ca66c', '1907cfc', 'a3a476f', 
  'a12ceae', 'ab4a830');

vcf::xen_hypervisor::check_version_and_report(app_info:app_info, fixes:fixes, severity:SECURITY_WARNING);

The latest version of this script can be found in these locations depending on your platform:

Linux / Unix:
/opt/nessus/lib/nessus/plugins/xen_server_XSA-383.nasl
Windows:
C:\ProgramData\Tenable\Nessus\nessus\plugins\xen_server_XSA-383.nasl
Mac OS X:
/Library/Nessus/run/lib/nessus/plugins/xen_server_XSA-383.nasl

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How to Run

Here is how to run the No memory limit for dom0less domUs (XSA-383) as a standalone plugin via the Nessus web user interface (https://localhost:8834/):

Click to start a New Scan.
Select Advanced Scan.
Navigate to the Plugins tab.
On the top right corner click to Disable All plugins.
On the left side table select Misc. plugin family.
On the right side table select No memory limit for dom0less domUs (XSA-383) plugin ID 159892.
Specify the target on the Settings tab and click to Save the scan.
Run the scan.

Here are a few examples of how to run the plugin in the command line. Note that the examples below demonstrate the usage on the Linux / Unix platform.

Basic usage:

/opt/nessus/bin/nasl xen_server_XSA-383.nasl -t <IP/HOST>

Run the plugin with audit trail message on the console:

/opt/nessus/bin/nasl -a xen_server_XSA-383.nasl -t <IP/HOST>

Run the plugin with trace script execution written to the console (useful for debugging):

/opt/nessus/bin/nasl -T - xen_server_XSA-383.nasl -t <IP/HOST>

Run the plugin with using a state file for the target and updating it (useful for running multiple plugins on the target):

/opt/nessus/bin/nasl -K /tmp/state xen_server_XSA-383.nasl -t <IP/HOST>

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References

IAVB | Information Assurance Vulnerability Bulletin:

2021-B-0061-S

See also:

Similar and related Nessus plugins:

153509 - Debian DSA-4977-1 : xen - security update
153108 - openSUSE 15 Security Update : xen (openSUSE-SU-2021:1236-1)
153009 - openSUSE 15 Security Update : xen (openSUSE-SU-2021:2923-1)
153016 - SUSE SLED15 / SLES15 Security Update : xen (SUSE-SU-2021:2922-1)
153010 - SUSE SLED15 / SLES15 Security Update : xen (SUSE-SU-2021:2923-1)
153017 - SUSE SLED12 / SLES12 Security Update : xen (SUSE-SU-2021:2924-1)
153013 - SUSE SLES15 Security Update : xen (SUSE-SU-2021:2925-1)
95630 - Xen Multiple Vulnerabilities (XSA-191 - XSA-198)
99399 - Xen Hypervisor XENMEM_exchange Memory Disclosure (XSA-212)
106902 - Xen Multiple Vulnerabilities (Spectre) (Meltdown) (XSA-254)
109727 - Xen Intel Architecture Debug Exception Handling Local Privilege Escalation (XSA-260)
112159 - Xen Project Speculative Execution Side Channel Vulnerability (XSA-273) (Foreshadow)
125389 - Xen Project Microarchitectural Data Sampling Speculative Side-Channel Vulnerabilities (MDSUM/RIDL) (MFBDS/RIDL/ZombieLoad) (MLPDS/RIDL) (MSBDS/Fallout) (XSA-297)
134172 - Xen Denial of Service vulnerability (XSA-304)
134174 - Xen Information Disclosure Vulnerability (XSA-305)
149085 - Xen Speculative Side Channel Information Disclosure (XSA-320)
159518 - Xen IOMMU page mapping issues on x86 (XSA-378)
156013 - Debian DSA-5019-1 : wireshark - security update
154825 - Wireshark 3.4.x < 3.4.6 DoS (macOS)
151433 - Photon OS 4.0: Wireshark PHSA-2021-4.0-0055
154824 - Wireshark 3.4.x < 3.4.6 DoS

Version

This page has been produced using Nessus Professional 10.1.2 (#68) LINUX, Plugin set 202205072148.
Plugin file xen_server_XSA-383.nasl version 1.3. For more plugins, visit the Nessus Plugin Library.

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No memory limit for dom0less domUs (XSA-383) - Nessus

Plugin Overview

Vulnerability Information

Synopsis

Description

Solution

Public Exploits

Risk Information

Plugin Source

How to Run

References

Version

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