Xen: missing IOMMU TLB flushing (XSA-442)

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

include('compat.inc');

if (description)
{
  script_id(182972);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/01/15");

  script_cve_id("CVE-2023-34326");
  script_xref(name:"IAVB", value:"2023-B-0081-S");

  script_name(english:"Xen: missing IOMMU TLB flushing (XSA-442)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Xen hypervisor installation is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The caching invalidation guidelines from the AMD-Vi specification (48882—Rev 3.07-PUB—Oct 2022) is incorrect on some 
hardware, as devices will malfunction (see stale DMA mappings) if some fields of the DTE are updated but the IOMMU
TLB is not flushed.

Such stale DMA mappings can point to memory ranges not owned by the guest, thus allowing access to unindented memory 
regions, leading to privilege escalation, denial of service (DoS) affecting the entire host, and information leaks.

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-442.html");
  script_set_attribute(attribute:"solution", value:
"Apply the appropriate patch according to the vendor advisory.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:C/I:C/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:L/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-2023-34326");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2023/10/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/10/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/10/12");

  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) 2023-2024 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['4.15']['fixed_ver']           = '4.15.5';
fixes['4.15']['fixed_ver_display']   = '4.15.5 (changeset 1b8dbe4)';
fixes['4.15']['affected_ver_regex']  = "^4\.15([^0-9]|$)";
fixes['4.15']['affected_changesets'] = make_list('0a70ce9', '3a9a290',
  'd7b7804', 'b007f82', 'dac9060', 'd39e5cf', 'd75cb6d', '93504b3', 
  '67b9743', '806893a', '094cd5c', 'db3386e', '0517763', 'da7f151');

fixes['4.17']['fixed_ver']           = '4.17.3';
fixes['4.17']['fixed_ver_display']   = '4.17.3-pre (changeset 0d8f9f7)';
fixes['4.17']['affected_ver_regex']  = "^4\.17([^0-9]|$)";
fixes['4.17']['affected_changesets'] = make_list('c4e05c9', '90c540c',
  '9ac2f49', '19ee1e1', '2e2c3ef', 'e4a71bc', '5f7efd4', 'ba023e9', 
  '3952c73', '84690fb', 'dc28aba', 'd2d2dca', 'd31e5b2', '699de51', 
  '8be85d8', 'a939e95', '7ca58fb', '0429822', 'ba360fb', '5116fe1', 
  'e08e733', '1bd4523', 'a885649', 'd0cdd34', 'f04295d', 'e5f9987', 
  '7b5155a', '052a8d2', 'f00d563', 'e418a77', '24487fe', 'ae1045c', 
  '37f1d68', '476d262', 'a1f68fb', '36e84ea', '56076ef', '1c3927f', 
  '8d84be5', '7d88979', '2f337a0');

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