Vulnerabilities > CVE-2020-0906 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Microsoft Excel, Office and Office 365 Proplus

047910
CVSS 9.3 - CRITICAL
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
network
microsoft
CWE-119
critical
nessus

Summary

A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory, aka 'Microsoft Excel Remote Code Execution Vulnerability'. This CVE ID is unique from CVE-2020-0979.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Nessus

  • NASL familyWindows : Microsoft Bulletins
    NASL idSMB_NT_MS20_APR_OFFICE.NASL
    descriptionThe Microsoft Office Products are missing security updates. It is, therefore, affected by multiple vulnerabilities : - A remote code execution vulnerability exists when Microsoft Office improperly loads arbitrary type libraries. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. (CVE-2020-0760) - A remote code execution vulnerability exists in Microsoft Word software when it fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could use a specially crafted file to perform actions in the security context of the current user. For example, the file could then take actions on behalf of the logged-on user with the same permissions as the current user. (CVE-2020-0980) - A remote code execution vulnerability exists in Microsoft Office software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. (CVE-2020-0991) - A remote code execution vulnerability exists when the Microsoft Office Access Connectivity Engine improperly handles objects in memory. An attacker who successfully exploited this vulnerability could execute arbitrary code on a victim system. An attacker could exploit this vulnerability by enticing a victim to open a specially crafted file. The update addresses the vulnerability by correcting the way the Microsoft Office Access Connectivity Engine handles objects in memory. (CVE-2020-0961) - A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. (CVE-2020-0906, CVE-2020-0979)
    last seen2020-04-18
    modified2020-04-14
    plugin id135476
    published2020-04-14
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/135476
    titleSecurity Updates for Microsoft Office Products (April 2020)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    # The descriptive text and package checks in this plugin were  
    # extracted from the Microsoft Security Updates API. The text
    # itself is copyright (C) Microsoft Corporation.
    #
    
    include('compat.inc');
    
    if (description)
    {
      script_id(135476);
      script_version("1.5");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/17");
    
      script_cve_id(
        "CVE-2020-0760",
        "CVE-2020-0906",
        "CVE-2020-0961",
        "CVE-2020-0979",
        "CVE-2020-0980",
        "CVE-2020-0991"
      );
      script_xref(name:"MSKB", value:"3128012");
      script_xref(name:"MSKB", value:"3203462");
      script_xref(name:"MSKB", value:"4011104");
      script_xref(name:"MSKB", value:"4484117");
      script_xref(name:"MSKB", value:"4484126");
      script_xref(name:"MSKB", value:"4484214");
      script_xref(name:"MSKB", value:"4484229");
      script_xref(name:"MSKB", value:"4484238");
      script_xref(name:"MSKB", value:"4484258");
      script_xref(name:"MSKB", value:"4484260");
      script_xref(name:"MSKB", value:"4484266");
      script_xref(name:"MSKB", value:"4484287");
      script_xref(name:"MSKB", value:"4484294");
      script_xref(name:"MSFT", value:"MS20-3128012");
      script_xref(name:"MSFT", value:"MS20-3203462");
      script_xref(name:"MSFT", value:"MS20-4011104");
      script_xref(name:"MSFT", value:"MS20-4484117");
      script_xref(name:"MSFT", value:"MS20-4484126");
      script_xref(name:"MSFT", value:"MS20-4484214");
      script_xref(name:"MSFT", value:"MS20-4484229");
      script_xref(name:"MSFT", value:"MS20-4484238");
      script_xref(name:"MSFT", value:"MS20-4484258");
      script_xref(name:"MSFT", value:"MS20-4484260");
      script_xref(name:"MSFT", value:"MS20-4484266");
      script_xref(name:"MSFT", value:"MS20-4484287");
      script_xref(name:"MSFT", value:"MS20-4484294");
      script_xref(name:"IAVA", value:"2020-A-0142");
    
      script_name(english:"Security Updates for Microsoft Office Products (April 2020)");
    
      script_set_attribute(attribute:"synopsis", value:
    "The Microsoft Office Products are affected by multiple vulnerabilities.");
      script_set_attribute(attribute:"description", value:
    "The Microsoft Office Products are missing security updates.
    It is, therefore, affected by multiple vulnerabilities :
    
      - A remote code execution vulnerability exists when
        Microsoft Office improperly loads arbitrary type
        libraries. An attacker could then install programs;
        view, change, or delete data; or create new accounts
        with full user rights. Users whose accounts are
        configured to have fewer user rights on the system could
        be less impacted than users who operate with
        administrative user rights.  (CVE-2020-0760)
    
      - A remote code execution vulnerability exists in
        Microsoft Word software when it fails to properly handle
        objects in memory. An attacker who successfully
        exploited the vulnerability could use a specially
        crafted file to perform actions in the security context
        of the current user. For example, the file could then
        take actions on behalf of the logged-on user with the
        same permissions as the current user.  (CVE-2020-0980)
    
      - A remote code execution vulnerability exists in
        Microsoft Office software when the software fails to
        properly handle objects in memory. An attacker who
        successfully exploited the vulnerability could run
        arbitrary code in the context of the current user. If
        the current user is logged on with administrative user
        rights, an attacker could take control of the affected
        system. An attacker could then install programs; view,
        change, or delete data; or create new accounts with full
        user rights.  (CVE-2020-0991)
    
      - A remote code execution vulnerability exists when the
        Microsoft Office Access Connectivity Engine improperly
        handles objects in memory. An attacker who successfully
        exploited this vulnerability could execute arbitrary
        code on a victim system. An attacker could exploit this
        vulnerability by enticing a victim to open a specially
        crafted file. The update addresses the vulnerability by
        correcting the way the Microsoft Office Access
        Connectivity Engine handles objects in memory.
        (CVE-2020-0961)
    
      - A remote code execution vulnerability exists in
        Microsoft Excel software when the software fails to
        properly handle objects in memory. An attacker who
        successfully exploited the vulnerability could run
        arbitrary code in the context of the current user. If
        the current user is logged on with administrative user
        rights, an attacker could take control of the affected
        system. An attacker could then install programs; view,
        change, or delete data; or create new accounts with full
        user rights.  (CVE-2020-0906, CVE-2020-0979)");
      # https://support.microsoft.com/en-us/help/3128012/security-update-for-office-2016-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c6907f9f");
      # https://support.microsoft.com/en-us/help/4484214/security-update-for-office-2016-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?22455c7d");
      # https://support.microsoft.com/en-us/help/4484260/security-update-for-office-2013-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6758cebc");
      # https://support.microsoft.com/en-us/help/4484266/security-update-for-office-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?19ff4b0c");
      # https://support.microsoft.com/en-us/help/4484287/security-update-for-office-2016-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?acbb3d03");
      # https://support.microsoft.com/en-us/help/4484294/security-update-for-office-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?5e18eb45");
      # https://support.microsoft.com/en-us/help/3203462/security-update-for-office-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?87117772");
      # https://support.microsoft.com/en-us/help/4484258/security-update-for-office-2016-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?cc8824f1");
      # https://support.microsoft.com/en-us/help/4484126/security-update-for-office-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a0a366b9");
      # https://support.microsoft.com/en-us/help/4011104/security-update-for-office-2013-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ee0e9939");
      # https://support.microsoft.com/en-us/help/4484117/security-update-for-office-2013-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?318ce33a");
      # https://support.microsoft.com/en-us/help/4484238/security-update-for-office-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?872a2ed0");
      # https://support.microsoft.com/en-us/help/4484229/security-update-for-office-2013-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?67e5e2db");
      script_set_attribute(attribute:"solution", value:
    "Microsoft has released security updates for Microsoft Office Products.
    
    For Office 365, Office 2016 C2R, or Office 2019, ensure automatic
    updates are enabled or open any office app and manually perform an
    update.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/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:N/UI:R/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-2020-0760");
    
      script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2020/04/14");
      script_set_attribute(attribute:"patch_publication_date", value:"2020/04/14");
      script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/14");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:office");
      script_set_attribute(attribute:"stig_severity", value:"II");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"Windows : Microsoft Bulletins");
    
      script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("office_installed.nasl", "smb_hotfixes.nasl", "ms_bulletin_checks_possible.nasl");
      script_require_keys("SMB/MS_Bulletin_Checks/Possible");
      script_require_ports(139, 445, "Host/patch_management_checks");
    
      exit(0);
    }
    
    include('smb_func.inc');
    include('smb_hotfixes.inc');
    include('smb_hotfixes_fcheck.inc');
    include('smb_reg_query.inc');
    include('install_func.inc');
    
    get_kb_item_or_exit('SMB/MS_Bulletin_Checks/Possible');
    
    bulletin = 'MS20-04';
    kbs = make_list(
      '3203462', # Office 2010 SP2
      '4484126', # Office 2010 SP2
      '4484238', # Office 2010 SP2
      '4484266', # Office 2010 SP2
      '4484294', # Office 2010 SP2
      '4011104', # Office 2013 SP1
      '4484117', # Office 2013 SP1
      '4484229', # Office 2013 SP1
      '4484260', # Office 2013 SP1
      '3128012', # Office 2016
      '4484214', # Office 2016
      '4484287', # Office 2016
      '4484258'  # Office 2016
    );
    
    if (get_kb_item('Host/patch_management_checks'))
      hotfix_check_3rd_party(bulletin:bulletin, kbs:kbs, severity:SECURITY_HOLE);
    
    get_kb_item_or_exit('SMB/Registry/Enumerated', exit_code:1);
    
    vuln = FALSE;
    port = kb_smb_transport();
    
    office_vers = hotfix_check_office_version();
    
    # Office 2010 SP2
    if (office_vers['14.0'])
    {
      office_sp = get_kb_item('SMB/Office/2010/SP');
      if (!isnull(office_sp) && office_sp == 2)
      {
        prod = 'Microsoft Office 2010 SP2';
    
        path = hotfix_get_officecommonfilesdir(officever:'14.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\VBA\\VBA7');
        kb = '3203462';
        file = 'vbe7.dll';
        version = '7.0.16.45';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'14.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE14');
        kb = '4484126';
        file = 'mso.dll';
        version = '14.0.7248.5000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'14.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE14');
        kb = '4484238';
        file = 'acecore.dll';
        version = '14.0.7248.5000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officeprogramfilesdir(officever:'14.0');
        path = hotfix_append_path(path:path, value:'Microsoft Office\\Office14');
        kb = '4484266';
        file = 'graph.exe';
        version = '14.0.7248.5000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        # wwlibcxm.dll only exists if KB2428677 is installed
        path = hotfix_get_officeprogramfilesdir(officever:'14.0');
        path = hotfix_append_path(path:path, value:'Microsoft Office\\Office14');
        kb = '4484294';
        file = 'wwlibcxm.dll';
        version = '14.0.7248.5000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
      }
    }
    
    # Office 2013 SP1
    if (office_vers['15.0'])
    {
      office_sp = get_kb_item('SMB/Office/2013/SP');
      if (!isnull(office_sp) && office_sp == 1)
      {
        prod = 'Microsoft Office 2013 SP1';
    
        path = hotfix_get_officecommonfilesdir(officever:'15.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\VBA\\VBA7.1');
        kb = '4011104';
        file = 'vbe7.dll';
        version = '7.1.10.96';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER )
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'15.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE15');
        kb = '4484117';
        file = 'mso.dll';
        version = '15.0.5233.1000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER )
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'15.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE15');
        kb = '4484229';
        file = 'acecore.dll';
        version = '15.0.5233.1000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER )
          vuln = TRUE;
    
        path = hotfix_get_officeprogramfilesdir(officever:'15.0');
        path = hotfix_append_path(path:path, value:'Microsoft Office\\Office15');
        kb = '4484260';
        file = 'graph.exe';
        version = '15.0.5233.1000';
        if (hotfix_check_fversion(file:file, version:version, path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER )
          vuln = TRUE;
      }
    }
    
    # Office 2016 / 2019 / C2R
    if (office_vers['16.0'])
    {
      office_sp = get_kb_item('SMB/Office/2016/SP');
      if (!isnull(office_sp) && office_sp == 0)
      {
        prod = 'Microsoft Office 2016';
    
        path = hotfix_get_officecommonfilesdir(officever:'16.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\VBA\\VBA7.1');
        kb = '3128012';
        file = 'vbe7.dll';
        version = '7.1.10.96';
        if (hotfix_check_fversion(file:file, version:version, channel:'MSI', channel_product:'Office', path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'16.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE16');
        kb = '4484214';
        file = 'mso.dll';
        version = '16.0.4993.1002';
        if (hotfix_check_fversion(file:file, version:version, channel:'MSI', channel_product:'Office', path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officecommonfilesdir(officever:'16.0');
        path = hotfix_append_path(path:path, value:'Microsoft Shared\\OFFICE16');
        kb = '4484287';
        file = 'acecore.dll';
        version = '16.0.4993.1000';
        if (hotfix_check_fversion(file:file, version:version, channel:'MSI', channel_product:'Office', path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        path = hotfix_get_officeprogramfilesdir(officever:'16.0');
        path = hotfix_append_path(path:path, value:'Microsoft Office\\Office16');
        kb = '4484258';
        file = 'graph.exe';
        version = '16.0.4993.1000';
        if (hotfix_check_fversion(file:file, version:version, channel:'MSI', channel_product:'Office', path:path, kb:kb, bulletin:bulletin, product:prod) == HCF_OLDER)
          vuln = TRUE;
    
        prod2019 = 'Microsoft Office 2019';
        path = hotfix_get_officeprogramfilesdir(officever:'16.0');
        path = hotfix_append_path(path:path, value:'Microsoft Office\\root\\Office16');
        if (
          hotfix_check_fversion(file:'graph.exe', version:'16.0.11328.20564', channel:'Deferred', channel_product:'Office', path:path, bulletin:bulletin, product:prod) == HCF_OLDER ||
          hotfix_check_fversion(file:'graph.exe', version:'16.0.11929.20708', channel:'Deferred', channel_version:'1908', channel_product:'Office', path:path, bulletin:bulletin, product:prod) == HCF_OLDER ||
          hotfix_check_fversion(file:'graph.exe', version:'16.0.12527.20442', channel:'First Release for Deferred', channel_product:'Office', path:path, bulletin:bulletin, product:prod) == HCF_OLDER ||
          hotfix_check_fversion(file:'graph.exe', version:'16.0.12624.20442', channel:'Current', channel_product:'Office', path:path, bulletin:bulletin, product:prod) == HCF_OLDER ||
          # 2019
          hotfix_check_fversion(file:'graph.exe', version:'16.0.12624.20442', channel:'2019 Retail', channel_product:'Office', path:path, bulletin:bulletin, product:prod2019) == HCF_OLDER ||
          hotfix_check_fversion(file:'graph.exe', version:'16.0.10358.20061', channel:'2019 Volume', channel_product:'Office', path:path, bulletin:bulletin, product:prod2019) == HCF_OLDER
        )
        vuln = TRUE;
      }
    }
    
    if (vuln)
    {
      replace_kb_item(name:'SMB/Missing/'+bulletin, value:TRUE);
      hotfix_security_hole();
      hotfix_check_fversion_end();
      exit(0);
    }
    else
    {
      hotfix_check_fversion_end();
      audit(AUDIT_HOST_NOT, 'affected');
    }
    
  • NASL familyWindows : Microsoft Bulletins
    NASL idSMB_NT_MS20_APR_EXCEL.NASL
    descriptionThe Microsoft Excel Products are missing security updates. It is, therefore, affected by multiple vulnerabilities : - A remote code execution vulnerability exists when Microsoft Office improperly loads arbitrary type libraries. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. (CVE-2020-0760) - A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. (CVE-2020-0906)
    last seen2020-05-08
    modified2020-04-14
    plugin id135474
    published2020-04-14
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/135474
    titleSecurity Updates for Microsoft Excel Products (April 2020)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    # The descriptive text and package checks in this plugin were  
    # extracted from the Microsoft Security Updates API. The text
    # itself is copyright (C) Microsoft Corporation.
    #
    
    include('compat.inc');
    
    if (description)
    {
      script_id(135474);
      script_version("1.5");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/05/06");
    
      script_cve_id("CVE-2020-0760", "CVE-2020-0906", "CVE-2020-0979");
      script_xref(name:"MSKB", value:"4484283");
      script_xref(name:"MSKB", value:"4484273");
      script_xref(name:"MSKB", value:"4484285");
      script_xref(name:"MSFT", value:"MS20-4484283");
      script_xref(name:"MSFT", value:"MS20-4484273");
      script_xref(name:"MSFT", value:"MS20-4484285");
      script_xref(name:"IAVA", value:"2020-A-0144");
    
      script_name(english:"Security Updates for Microsoft Excel Products (April 2020)");
    
      script_set_attribute(attribute:"synopsis", value:
    "The Microsoft Excel Products are affected by multiple vulnerabilities.");
      script_set_attribute(attribute:"description", value:
    "The Microsoft Excel Products are missing security updates.
    It is, therefore, affected by multiple vulnerabilities :
    
      - A remote code execution vulnerability exists when
        Microsoft Office improperly loads arbitrary type
        libraries. An attacker could then install programs;
        view, change, or delete data; or create new accounts
        with full user rights. Users whose accounts are
        configured to have fewer user rights on the system could
        be less impacted than users who operate with
        administrative user rights.  (CVE-2020-0760)
    
      - A remote code execution vulnerability exists in
        Microsoft Excel software when the software fails to
        properly handle objects in memory. An attacker who
        successfully exploited the vulnerability could run
        arbitrary code in the context of the current user. If
        the current user is logged on with administrative user
        rights, an attacker could take control of the affected
        system. An attacker could then install programs; view,
        change, or delete data; or create new accounts with full
        user rights.  (CVE-2020-0906)");
      # https://support.microsoft.com/en-us/help/4484283/security-update-for-excel-2013-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a9f68ebb");
      # https://support.microsoft.com/en-us/help/4484273/security-update-for-excel-2016-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?723b63ab");
      # https://support.microsoft.com/en-us/help/4484285/security-update-for-excel-2010-april-14-2020
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?771d8248");
      script_set_attribute(attribute:"solution", value:
    "Microsoft has released the following security updates to address this issue:  
      -KB4484283
      -KB4484273
      -KB4484285
    
    For Office 365, Office 2016 C2R, or Office 2019, ensure automatic
    updates are enabled or open any office app and manually perform an
    update.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/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:N/AC:L/PR:N/UI:R/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-2020-0906");
    
      script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2020/04/14");
      script_set_attribute(attribute:"patch_publication_date", value:"2020/04/14");
      script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/14");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:excel");
      script_set_attribute(attribute:"stig_severity", value:"II");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"Windows : Microsoft Bulletins");
    
      script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("office_installed.nasl", "microsoft_office_compatibility_pack_installed.nbin", "smb_hotfixes.nasl", "ms_bulletin_checks_possible.nasl");
      script_require_keys("SMB/MS_Bulletin_Checks/Possible");
      script_require_ports(139, 445, "Host/patch_management_checks");
    
      exit(0);
    }
    
    include('audit.inc');
    include('smb_func.inc');
    include('smb_hotfixes.inc');
    include('smb_hotfixes_fcheck.inc');
    include('smb_reg_query.inc');
    include('install_func.inc');
    
    global_var vuln;
    
    get_kb_item_or_exit('SMB/MS_Bulletin_Checks/Possible');
    
    bulletin = 'MS20-04';
    kbs = make_list(
      '4484283',
      '4484273',
      '4484285'
    );
    
    if (get_kb_item('Host/patch_management_checks'))
      hotfix_check_3rd_party(bulletin:bulletin, kbs:kbs, severity:SECURITY_HOLE);
    
    get_kb_item_or_exit('SMB/Registry/Enumerated', exit_code:1);
    
    port = kb_smb_transport();
    
    checks = make_array(
      '14.0', make_array('sp', 2, 'version', '14.0.7248.5000', 'kb', '4484285'),
      '15.0', make_array('sp', 1, 'version', '15.0.5233.1000', 'kb', '4484283'),
      '16.0', make_nested_list(
        make_array('sp', 0, 'version', '16.0.4993.1001', 'channel', 'MSI', 'kb', '4484273'),
        # C2R
        make_array('version', '16.0.11328.20564', 'channel', 'Deferred'),
        make_array('version', '16.0.11929.20708', 'channel', 'Deferred', 'channel_version', '1908'),
        make_array('version', '16.0.12527.20442', 'channel', 'First Release for Deferred'),
        make_array('version', '16.0.12624.20442', 'channel', 'Current'),
        # 2019
        make_array('version', '16.0.12624.20442', 'channel', '2019 Retail'),
        make_array('version', '16.0.10358.20061', 'channel', '2019 Volume')
        )
      );
    
    if (hotfix_check_office_product(product:'Excel', checks:checks, bulletin:bulletin))
    {
      replace_kb_item(name:'SMB/Missing/'+bulletin, value:TRUE);
      hotfix_security_hole();
      hotfix_check_fversion_end();
      exit(0);
    }
    else
    {
      hotfix_check_fversion_end();
      audit(AUDIT_HOST_NOT, 'affected');
    }