Xen oxenstored DoS (XSA-352)

##
# (C) Tenable Network Security, Inc.
##

include('compat.inc');

if (description)
{
  script_id(144651);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/06/03");

  script_cve_id("CVE-2020-29486");
  script_xref(name:"IAVB", value:"2020-B-0077-S");

  script_name(english:"Xen oxenstored DoS (XSA-352)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Xen hypervisor installation is missing a security update.");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by a denial
of service vulnerability due to an issue with oxenstored. A malicious guest administrator can change xenstore node
ownership to run another guest out of quota, or create an unbounded number of nodes owned by dom0 to run xenstored out
of memory. This can cause a specific guest or the system to stop responding.

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-352.html");
  script_set_attribute(attribute:"solution", value:
"Apply the appropriate patch or workaround according to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/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:L/AC:L/PR:H/UI:N/S:C/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-2020-29486");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/12/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/12/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/12/31");

  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:"II");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2020-2021 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');

app = 'Xen Hypervisor';

app_info = vcf::xen_hypervisor::get_app_info(app:app);

if (report_paranoia < 2) audit(AUDIT_PARANOID);
fixes['4.10']['fixed_ver']           = '4.10.4';
fixes['4.10']['fixed_ver_display']   = '4.10.4 (changeset fef52f1)';
fixes['4.10']['affected_ver_regex']  = "^4\.10\.";
fixes['4.10']['affected_changesets'] = make_list('7073b82', '3056f89',
  '03569ab', '17b26b8', '66e2db1', 'fcc17dc', 'e644edc', '7e16a0e',
  'a4c2c94', 'bdd36b6', '59dc712', '57a55a4', '03937f9', 'f06e4ac',
  '3658044', '9edd614', '8cb4d2d', '2fee46c', '06092d1', '77d6b2b',
  'a043a64', '3afd384', 'e8231b6', '1d72d99', '8eb5328', 'f79f47f',
  'f91d2a9', '1fdcfdb', '17ec9b4', '15b2980', '398f91c', '5114e77',
  '7a4ec79', '78d903e', '2012db4', '71da63b', '56f8da7', 'd73e972',
  '6f012ec', '75a05da', 'c334b87', '07ad8ff', '1719f79', 'f58caa4',
  'f2befb6', '83b7f04', 'e081568', '7f0793a', '8fac37e', 'baf80b6',
  '5402540', 'f85223f', '635ae12', '3d14937', '4218b74', '93be943',
  '4418841', 'd9c67d3', '8976bab', '388e303', '0b0a155', '9df4399',
  'fd57038', 'a9bda69', 'a380168', 'c1a4914', '6261a06', 'fd6e49e',
  'bd20589', 'ce05683', '934d6e1', '6e636f2', 'dfc0b23', '2f83654',
  'bf467cc', '6df4d40', 'e20bb58', 'a1a9b05', 'afca67f', 'b922c44',
  'b413732', '3d60903', 'b01c84e', '1e722e6', '59cf3a0', 'fabfce8',
  'a4dd2fe', '6e63a6f', '24d62e1', 'cbedabf', '38e589d', 'a91b8fc',
  '3e0c316', '49a5d6e', '6cb1cb9', 'ba2776a', '9d143e8', 'fe8dab3',
  '07e546e', 'fefa5f9', 'c9f9ff7', '406d40d', 'e489955', '37139f1',
  'fde09cb', '804ba02', 'e8c3971', 'a8c4293', 'aa40452', '1da3dab',
  'e5632c4', '902e72d', '6a14610', 'ea815b2', '13ad331', '61b75d9',
  'e70e7bf', 'e966e2e', 'dfa16a1', 'a71e199', 'c98be9e', 'a548e10',
  'd3c0e84', '53b1572', '7203f9a', '6d1659d', 'a782173', '24e90db',
  '0824bc6', 'e6f3135', '3131bf9');

fixes['4.11']['fixed_ver']           = '4.11.4';
fixes['4.11']['fixed_ver_display']   = '4.11.4 (changeset f1f3dee)';
fixes['4.11']['affected_ver_regex']  = "^4\.11\.";
fixes['4.11']['affected_changesets'] = make_list('1e87058', '4cc2387',
  '4053771', 'b3f4121', 'e36f81f', '1034a45', '7791d2e', '5724431',
  '495e973', '771a105', 'b3f80a3', '966f266', '57261ac', '1b7ed67',
  '0a6bbf9', '6be47ee', '2fe5a55', '36621b7', '88f6ff5', '170445f',
  '550387f', '0297770', 'd2b6bf9', '41a822c', '8ab4af9', '4fe1326',
  '4438fc1', '2a730d5', '62aed78', '1447d44', '3b5de11', '65fad0a',
  'b5eb495', 'e274c8b', '1d021db', '63199df', '7739ffd', '4f35f7f',
  '490c517', '7912bbe', 'f5ec9f2', 'ad7d040', '3630a36', '3263f25',
  '3e565a9', '30b3f29', '3def846', 'cc1561a', '6e9de08', '13f60bf',
  '9703a2f', '7284bfa', '2fe163d', '2031bd3', '7bf4983', '7129b9e',
  'ddaaccb', 'e6ddf4a', 'f2bc74c', 'd623658', '37c853a', '8bf72ea',
  '2d11e6d', '4ed0007', '7def72c', '18be3aa', 'a3a392e', 'e96cdba',
  '2b77729', '9be7992', 'b8d476a', '1c751c4', '7dd2ac3', 'a58bba2',
  '7d8fa6a', '4777208', '48e8564', '2efca7e', 'afe82f5', 'e84b634', '96a8b5b');

fixes['4.12']['fixed_ver']           = '4.12.4';
fixes['4.12']['fixed_ver_display']   = '4.12.4 (changeset 3c13a87)';
fixes['4.12']['affected_ver_regex']  = "^4\.12\.";
fixes['4.12']['affected_changesets'] = make_list('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']           = '4.13.3';
fixes['4.13']['fixed_ver_display']   = '4.13.3-pre (changeset a2f7ae1)';
fixes['4.13']['affected_ver_regex']  = "^4\.13\.";
fixes['4.13']['affected_changesets'] = make_list('d6a55f1', 'c6196ca',
  '18c0abb', '782aa4b', '6aea4d8', '12a41a8', '4056c3e', 'f4d84a2',
  '65c187f', '2df79ff', 'b693968', '52a0a8f', '60e3727', '8cc0a86',
  'ef765f6', 'b8f23da', 'ee416da', '1819c9d', '1ab192f', '2007c63',
  '2948458', '4959626', '2fa586c', 'b530227', '74c5729', 'a1d8a6c',
  'd064b65', '4f30743', '72031bc', '7d6f52d', 'ec09215');

fixes['4.14']['fixed_ver']           = '4.14.1';
fixes['4.14']['fixed_ver_display']   = '4.14.1-pre (changeset 13268c5)';
fixes['4.14']['affected_ver_regex']  = "^4\.14\.";
fixes['4.14']['affected_changesets'] = make_list('de822c4', '57bbcd0',
  '7214cc7', '49ed711', 'dc871dd', 'b1c5e40', '61d3863', '9e53440',
  '335ef5b', '6fa3e05', 'f4405b6', '228e562', '0a79a1b', '5073c6b',
  '5259358', '3d0e1a1', '117521e', '91992c7', '4e298fa', '3beffb3',
  'da67712', '9c898a8', 'f130d5f', '1d1d1f5', '72bd989', '8e6c236',
  '1cfb9b1', '7c6ee4e', 'd11d977', '1ad1773', '0057b1f', 'd101b41',
  'd95f450', '73a0927', 'a38060e', '78a53f0', '89ae1b1', '7398a44',
  '59b8366', '1f9f1cb', 'f728b2d', '71a12a9', '0c96e42', '29b48aa',
  'd131310', '7d2b21f', 'f61c5d0', 'fc8fab1', '898864c', '9f954ae',
  '5784d1e', '10bb63c', '941f69a', '7b1e587', 'ee47e8e', '4ba3fb0',
  'd2ba323', 'b081a5f', 'e936515', '9c1cc64', '829dbe2', '8d14800',
  '0521dc9', '64c3951', '0974e00', 'a279fcb', 'f7ab0c1', '7339975',
  '94c157f', '79f1701', '9e757fc', '809a70b', 'b427109', 'c93b520',
  'f37a1cf', '5478934', '43eceee', '03019c2', '66cdf34', 'ecc6428',
  '2ee270e', '9b9fc8e', 'b8c2efb', 'f546906', 'eb4a543', 'e417504',
  '0bc4177', '5ad3152', 'fc8200a', '5eab5f0', 'b04d673', '28855eb',
  '174be04', '158c3bd', '3535f23', 'de7e543', '483b43c', '431d52a',
  'ceafff7', '369e7a3', '98aa6ea', '80dec06', '5482c28', 'edf5b86',
  'eca6d5e', 'c3a0fc2', '864d570', 'afed8e4', 'a5dab0a', 'b8c3e33', 'f836759');

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