Vulnerabilities > CVE-2016-1750 - Use After Free vulnerability in Apple products

047910
CVSS 9.3 - CRITICAL
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
network
apple
CWE-416
critical
nessus

Summary

Use-after-free vulnerability in the kernel in Apple iOS before 9.3, OS X before 10.11.4, tvOS before 9.2, and watchOS before 2.2 allows attackers to execute arbitrary code in a privileged context via a crafted app. <a href="http://cwe.mitre.org/data/definitions/416.html" rel="nofollow">CWE-416: Use After Free</a>

Vulnerable Configurations

Part Description Count
OS
Apple
283

Common Weakness Enumeration (CWE)

Nessus

  • NASL familyMisc.
    NASL idAPPLETV_9_2.NASL
    descriptionAccording to its banner, the remote Apple TV device is a version prior to 9.2. It is, therefore, affected by the following vulnerabilities : - An XML external entity (XXE) expansion flaw exists in libxml2 due to the XML parser accepting entities from untrusted sources. An unauthenticated, remote attacker can exploit this, via crafted XML data, to cause a denial of service through resource exhaustion. (CVE-2015-1819) - An XML external entity (XXE) injection flaw exists in libxml2 in file parser.c due to the XML parser accepting entities from untrusted sources. An unauthenticated, remote attacker can exploit this, via crafted XML data, to cause a denial of service or to disclose sensitive information. (CVE-2015-5312) - A heap buffer overflow condition exists in libxml2 in the xmlGROW() function within file parser.c while handling XML data. An unauthenticated, remote attacker can exploit this to disclose sensitive information. (CVE-2015-7499) - An out-of-bounds heap read error exists in libxml2 in the xmlParseMisc() function within file parser.c while handling entity boundaries. An unauthenticated, remote attacker can exploit this to cause a denial of service. (CVE-2015-7500) - An out-of-bounds read error exists in libxml2 in the xmlParseConditionalSections() function within file parser.c due to a failure to properly skip intermediary entities when it stops parsing invalid input. An unauthenticated, remote attacker can exploit this, via crafted XML data, to cause a denial of service. (CVE-2015-7942) - A flaw exists in libxml2 in the xz_decomp() function within file xzlib.c due to a failure to properly detect compression errors when handling compressed XML content. An unauthenticated, remote attacker can exploit this, via crafted XML data, to cause an infinite loop, resulting in a denial of service. (CVE-2015-8035) - A out-of-bounds read error exists in libxml2 in the xmlSAX2TextNode() function within file SAX2.c due to improper sanitization of input data. An unauthenticated, remote attacker can exploit this, via crafted XML data, to cause a denial of service or to disclose sensitive information. (CVE-2015-8242) - A use-after-free error exists in Nghttp2 within file lib/nghttp2_session.c when handling idle streams. An unauthenticated, remote attacker can exploit this to deference already freed memory, allowing the execution of arbitrary code. (CVE-2015-8659) - An overflow condition exists in the Broadcom Wi-Fi driver due to improper validation of data while handling SSID or WPS_ID_DEVICE_NAME values. An unauthenticated, adjacent attacker can exploit this, via a crafted wireless control message packet, to cause a denial of service or to execute arbitrary code. (CVE-2016-0801) - An overflow condition exists in the Broadcom Wi-Fi driver due to improper validation of user-supplied input when handling the packet length of event messages. An unauthenticated, adjacent attacker can exploit this, via a crafted wireless control message packet, to cause a denial of service or to execute arbitrary code. (CVE-2016-0802) - A flaw exists in FontParser due to improper validation of user-supplied input when handling encoded fonts that contain invalid characters. An unauthenticated, remote attacker can exploit this, via a crafted PDF document, to corrupt memory, resulting in a denial of service or the execution arbitrary code. (CVE-2016-1740) - A flaw exists in IOHIDFamily due to improper validation of user-supplied input. An unauthenticated, remote attacker can exploit this, via a crafted application, to gain access to kernel memory layout information. (CVE-2016-1748) - A use-after-free error exists in the kernel that allows an unauthenticated, remote attacker to execute arbitrary code via a crafted application. (CVE-2016-1750) - A flaw exists in the kernel due to a failure to properly restrict execution permissions. An unauthenticated, remote attacker can exploit this, via a crafted application, to bypass code-signing protection mechanisms. (CVE-2016-1751) - An unspecified flaw exists in the kernel that allows a local attacker to cause a denial of service via a crafted application. (CVE-2016-1752) - An integer overflow condition exists in the kernel due to improper validation of user-supplied input. An unauthenticated, remote attacker can exploit this, via a crafted application, to gain elevated privileges. (CVE-2016-1753) - A memory corruption issue exists in the kernel due to improper validation of user-supplied input. An unauthenticated, remote attacker can exploit this, by convincing a user to install a malicious application, to cause a denial of service or execute arbitrary code. CVE-2016-1754) - A use-after-free error exists in the AppleKeyStore user client when handling multiple threads, which is triggered when one thread closes the user client while another attempts to call an external method. An unauthenticated, remote attacker can exploit this, by convincing a user to install a malicious application, to execute arbitrary code with elevated privileges. (CVE-2016-1755) - A flaw exists in libxml2 due to improper validation of user-supplied input while handling XML content. An unauthenticated, remote attacker can exploit this, via a crafted XML document, to cause a denial of service or to execute arbitrary code. (CVE-2016-1762) - An out-of-bounds write error exists in TrueTypeScaler due to improper validation of user-supplied input while handling bdat tables in TTF fonts. An unauthenticated, remote attacker can exploit this, via a crafted TTF font, to cause a denial or service or to execute arbitrary code. (CVE-2016-1775) - A flaw exists in WebKit due to improper validation of user-supplied input. An unauthenticated, remote attacker can exploit this, via a crafted website, to cause a denial of service or execute arbitrary code. (CVE-2016-1783) - An unspecified flaw exists in the History implementation of WebKit that allows an unauthenticated, remote attacker to cause a denial of service via a crafted website. (CVE-2016-1784) - A heap buffer overflow condition exists in Mozilla Network Security Services due to improper validation of user-supplied input while parsing ASN.1 structures. An unauthenticated, remote attacker can exploit this, via crafted ASN.1 data in an X.509 certificate, to cause a denial of service or execute arbitrary code. (CVE-2016-1950) Note that only 4th generation models are affected by these vulnerabilities, and this plugin only checks these models.
    last seen2020-06-01
    modified2020-06-02
    plugin id90309
    published2016-04-01
    reporterThis script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/90309
    titleApple TV < 9.2 Multiple Vulnerabilities
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(90309);
      script_version("1.15");
      script_cvs_date("Date: 2019/11/19");
    
      script_cve_id(
        "CVE-2015-1819",
        "CVE-2015-5312",
        "CVE-2015-7499",
        "CVE-2015-7500",
        "CVE-2015-7942",
        "CVE-2015-8035",
        "CVE-2015-8242",
        "CVE-2015-8659",
        "CVE-2016-0801",
        "CVE-2016-0802",
        "CVE-2016-1740",
        "CVE-2016-1748",
        "CVE-2016-1750",
        "CVE-2016-1751",
        "CVE-2016-1752",
        "CVE-2016-1753",
        "CVE-2016-1754",
        "CVE-2016-1755",
        "CVE-2016-1762",
        "CVE-2016-1775",
        "CVE-2016-1783",
        "CVE-2016-1784",
        "CVE-2016-1950"
      );
      script_bugtraq_id(
        75570,
        77390,
        77681,
        79507,
        79509,
        79536,
        79562,
        80438
      );
      script_xref(name:"APPLE-SA", value:"APPLE-SA-2016-03-21-3");
    
      script_name(english:"Apple TV < 9.2 Multiple Vulnerabilities");
      script_summary(english:"Checks the build number.");
    
      script_set_attribute(attribute:"synopsis", value:
    "The remote device is affected by multiple vulnerabilities.");
      script_set_attribute(attribute:"description", value:
    "According to its banner, the remote Apple TV device is a version prior
    to 9.2. It is, therefore, affected by the following vulnerabilities :
    
      - An XML external entity (XXE) expansion flaw exists in
        libxml2 due to the XML parser accepting entities from
        untrusted sources. An unauthenticated, remote attacker
        can exploit this, via crafted XML data, to cause a
        denial of service through resource exhaustion.
        (CVE-2015-1819)
    
      - An XML external entity (XXE) injection flaw exists in
        libxml2 in file parser.c due to the XML parser accepting
        entities from untrusted sources. An unauthenticated,
        remote attacker can exploit this, via crafted XML data,
        to cause a denial of service or to disclose sensitive
        information. (CVE-2015-5312)
    
      - A heap buffer overflow condition exists in libxml2 in
        the xmlGROW() function within file parser.c while
        handling XML data. An unauthenticated, remote attacker
        can exploit this to disclose sensitive information.
        (CVE-2015-7499)
    
      - An out-of-bounds heap read error exists in libxml2 in
        the xmlParseMisc() function within file parser.c while
        handling entity boundaries. An unauthenticated, remote
        attacker can exploit this to cause a denial of service.
        (CVE-2015-7500)
    
      - An out-of-bounds read error exists in libxml2 in the
        xmlParseConditionalSections() function within file
        parser.c due to a failure to properly skip intermediary
        entities when it stops parsing invalid input. An
        unauthenticated, remote attacker can exploit this, via
        crafted XML data, to cause a denial of service.
        (CVE-2015-7942)
    
      - A flaw exists in libxml2 in the xz_decomp() function
        within file xzlib.c due to a failure to properly detect
        compression errors when handling compressed XML content.
        An unauthenticated, remote attacker can exploit this,
        via crafted XML data, to cause an infinite loop,
        resulting in a denial of service.
        (CVE-2015-8035)
    
      - A out-of-bounds read error exists in libxml2 in the
        xmlSAX2TextNode() function within file SAX2.c due to
        improper sanitization of input data. An unauthenticated,
        remote attacker can exploit this, via crafted XML data,
        to cause a denial of service or to disclose sensitive
        information. (CVE-2015-8242)
    
      - A use-after-free error exists in Nghttp2 within file
        lib/nghttp2_session.c when handling idle streams. An
        unauthenticated, remote attacker can exploit this to
        deference already freed memory, allowing the execution
        of arbitrary code. (CVE-2015-8659)
    
      - An overflow condition exists in the Broadcom Wi-Fi
        driver due to improper validation of data while handling
        SSID or WPS_ID_DEVICE_NAME values. An unauthenticated,
        adjacent attacker can exploit this, via a crafted
        wireless control message packet, to cause a denial of
        service or to execute arbitrary code. (CVE-2016-0801)
    
      - An overflow condition exists in the Broadcom Wi-Fi
        driver due to improper validation of user-supplied
        input when handling the packet length of event messages.
        An unauthenticated, adjacent attacker can exploit this,
        via a crafted wireless control message packet, to cause
        a denial of service or to execute arbitrary code.
        (CVE-2016-0802)
    
      - A flaw exists in FontParser due to improper validation
        of user-supplied input when handling encoded fonts that
        contain invalid characters. An unauthenticated, remote
        attacker can exploit this, via a crafted PDF document,
        to corrupt memory, resulting in a denial of service or
        the execution arbitrary code. (CVE-2016-1740)
    
      - A flaw exists in IOHIDFamily due to improper validation
        of user-supplied input. An unauthenticated, remote
        attacker can exploit this, via a crafted application,
        to gain access to kernel memory layout information.
        (CVE-2016-1748)
    
      - A use-after-free error exists in the kernel that allows
        an unauthenticated, remote attacker to execute arbitrary
        code via a crafted application. (CVE-2016-1750)
    
      - A flaw exists in the kernel due to a failure to properly
        restrict execution permissions. An unauthenticated,
        remote attacker can exploit this, via a crafted
        application, to bypass code-signing protection
        mechanisms. (CVE-2016-1751)
    
      - An unspecified flaw exists in the kernel that allows a
        local attacker to cause a denial of service via a
        crafted application. (CVE-2016-1752)
    
      - An integer overflow condition exists in the kernel due
        to improper validation of user-supplied input. An
        unauthenticated, remote attacker can exploit this, via
        a crafted application, to gain elevated privileges.
        (CVE-2016-1753)
    
      - A memory corruption issue exists in the kernel due to
        improper validation of user-supplied input. An
        unauthenticated, remote attacker can exploit this, by
        convincing a user to install a malicious application,
        to cause a denial of service or execute arbitrary code.
        CVE-2016-1754)
    
      - A use-after-free error exists in the AppleKeyStore user
        client when handling multiple threads, which is
        triggered when one thread closes the user client while
        another attempts to call an external method. An
        unauthenticated, remote attacker can exploit this, by
        convincing a user to install a malicious application, to
        execute arbitrary code with elevated privileges.
        (CVE-2016-1755)
    
      - A flaw exists in libxml2 due to improper validation of
        user-supplied input while handling XML content. An
        unauthenticated, remote attacker can exploit this, via a
        crafted XML document, to cause a denial of service or to
        execute arbitrary code. (CVE-2016-1762)
    
      - An out-of-bounds write error exists in TrueTypeScaler
        due to improper validation of user-supplied input while
        handling bdat tables in TTF fonts. An unauthenticated,
        remote attacker can exploit this, via a crafted TTF
        font, to cause a denial or service or to execute
        arbitrary code. (CVE-2016-1775)
    
      - A flaw exists in WebKit due to improper validation of
        user-supplied input. An unauthenticated, remote attacker
        can exploit this, via a crafted website, to cause a
        denial of service or execute arbitrary code.
        (CVE-2016-1783)
    
      - An unspecified flaw exists in the History implementation
        of WebKit that allows an unauthenticated, remote
        attacker to cause a denial of service via a crafted
        website. (CVE-2016-1784)
    
      - A heap buffer overflow condition exists in Mozilla
        Network Security Services due to improper validation of
        user-supplied input while parsing ASN.1 structures. An
        unauthenticated, remote attacker can exploit this, via
        crafted ASN.1 data in an X.509 certificate, to cause a
        denial of service or execute arbitrary code.
        (CVE-2016-1950)
    
    Note that only 4th generation models are affected by these
    vulnerabilities, and this plugin only checks these models.");
      script_set_attribute(attribute:"see_also", value:"https://support.apple.com/en-us/HT206169");
      # http://prod.lists.apple.com/archives/security-announce/2016/Mar/msg00002.html
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?5c691f32");
      script_set_attribute(attribute:"solution", value:
    "Upgrade to Apple TV version 9.2 or later. Note that this update is
    available only for 4th generation models.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
      script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H");
      script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
      script_set_attribute(attribute:"cvss_score_source", value:"CVE-2015-8659");
    
      script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
      script_set_attribute(attribute:"exploit_available", value:"true");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2015/02/22");
      script_set_attribute(attribute:"patch_publication_date", value:"2016/03/21");
      script_set_attribute(attribute:"plugin_publication_date", value:"2016/04/01");
    
      script_set_attribute(attribute:"plugin_type", value:"remote");
      script_set_attribute(attribute:"cpe", value:"cpe:/a:apple:apple_tv");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"Misc.");
    
      script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("appletv_version.nasl");
      script_require_keys("AppleTV/Version", "AppleTV/URL", "AppleTV/Port");
      script_require_ports("Services/www", 7000);
    
      exit(0);
    }
    
    include("appletv_func.inc");
    include("audit.inc");
    
    url = get_kb_item('AppleTV/URL');
    if (empty_or_null(url)) exit(0, 'Cannot determine Apple TV URL.');
    port = get_kb_item('AppleTV/Port');
    if (empty_or_null(port)) exit(0, 'Cannot determine Apple TV port.');
    
    build = get_kb_item('AppleTV/Version');
    if (empty_or_null(build)) audit(AUDIT_UNKNOWN_DEVICE_VER, 'Apple TV');
    
    model = get_kb_item('AppleTV/Model');
    if (empty_or_null(model)) exit(0, 'Cannot determine Apple TV model.');
    
    # fix
    fixed_build = "13Y234";
    tvos_ver = "9.2"; # for reporting purposes only
    
    # determine gen from the model
    gen = APPLETV_MODEL_GEN[model];
    
    appletv_check_version(
      build        : build,
      fix          : fixed_build,
      affected_gen : 4,
      fix_tvos_ver : tvos_ver,
      model        : model,
      gen          : gen,
      severity     : SECURITY_HOLE,
      port         : port,
      url          : url
    );
    
  • NASL familyMacOS X Local Security Checks
    NASL idMACOSX_10_11_4.NASL
    descriptionThe remote host is running a version of Mac OS X that is 10.11.x prior to 10.11.4. It is, therefore, affected by multiple vulnerabilities in the following components : - apache_mod_php - AppleRAID - AppleUSBNetworking - Bluetooth - Carbon - dyld - FontParser - HTTPProtocol - Intel Graphics Driver - IOFireWireFamily - IOGraphics - IOHIDFamily - IOUSBFamily - Kernel - libxml2 - Messages - NVIDIA Graphics Drivers - OpenSSH - OpenSSL - Python - QuickTime - Reminders - Ruby - Security - Tcl - TrueTypeScaler - Wi-Fi Note that successful exploitation of the most serious issues can result in arbitrary code execution.
    last seen2020-06-01
    modified2020-06-02
    plugin id90096
    published2016-03-22
    reporterThis script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/90096
    titleMac OS X 10.11.x < 10.11.4 Multiple Vulnerabilities
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(90096);
      script_version("1.17");
      script_cvs_date("Date: 2019/11/20");
    
      script_cve_id(
        "CVE-2014-9495",
        "CVE-2015-0973",
        "CVE-2015-1819",
        "CVE-2015-3195",
        "CVE-2015-5312",
        "CVE-2015-7499",
        "CVE-2015-7500",
        "CVE-2015-7551",
        "CVE-2015-7942",
        "CVE-2015-8035",
        "CVE-2015-8126",
        "CVE-2015-8242",
        "CVE-2015-8472",
        "CVE-2015-8659",
        "CVE-2016-0777",
        "CVE-2016-0778",
        "CVE-2016-0801",
        "CVE-2016-0802",
        "CVE-2016-1732",
        "CVE-2016-1733",
        "CVE-2016-1734",
        "CVE-2016-1735",
        "CVE-2016-1736",
        "CVE-2016-1737",
        "CVE-2016-1738",
        "CVE-2016-1740",
        "CVE-2016-1741",
        "CVE-2016-1743",
        "CVE-2016-1744",
        "CVE-2016-1745",
        "CVE-2016-1746",
        "CVE-2016-1747",
        "CVE-2016-1748",
        "CVE-2016-1749",
        "CVE-2016-1750",
        "CVE-2016-1752",
        "CVE-2016-1753",
        "CVE-2016-1754",
        "CVE-2016-1755",
        "CVE-2016-1756",
        "CVE-2016-1757",
        "CVE-2016-1758",
        "CVE-2016-1759",
        "CVE-2016-1761",
        "CVE-2016-1762",
        "CVE-2016-1764",
        "CVE-2016-1767",
        "CVE-2016-1768",
        "CVE-2016-1769",
        "CVE-2016-1770",
        "CVE-2016-1773",
        "CVE-2016-1775",
        "CVE-2016-1788",
        "CVE-2016-1950"
      );
      script_bugtraq_id(
        71820,
        71994,
        75570,
        77390,
        77568,
        77681,
        78624,
        78626,
        79507,
        79509,
        79536,
        79562,
        80438,
        80695,
        80698
      );
      script_xref(name:"APPLE-SA", value:"APPLE-SA-2016-03-21-5");
    
      script_name(english:"Mac OS X 10.11.x < 10.11.4 Multiple Vulnerabilities");
      script_summary(english:"Checks the version of Mac OS X.");
    
      script_set_attribute(attribute:"synopsis", value:
    "The remote Mac OS X host is affected by multiple vulnerabilities.");
      script_set_attribute(attribute:"description", value:
    "The remote host is running a version of Mac OS X that is 10.11.x prior
    to 10.11.4. It is, therefore, affected by multiple vulnerabilities in
    the following components :
    
      - apache_mod_php
      - AppleRAID
      - AppleUSBNetworking
      - Bluetooth
      - Carbon
      - dyld
      - FontParser
      - HTTPProtocol
      - Intel Graphics Driver
      - IOFireWireFamily
      - IOGraphics
      - IOHIDFamily
      - IOUSBFamily
      - Kernel
      - libxml2
      - Messages
      - NVIDIA Graphics Drivers
      - OpenSSH
      - OpenSSL
      - Python
      - QuickTime
      - Reminders
      - Ruby
      - Security
      - Tcl
      - TrueTypeScaler
      - Wi-Fi
    
    Note that successful exploitation of the most serious issues can
    result in arbitrary code execution.");
      script_set_attribute(attribute:"see_also", value:"https://support.apple.com/en-us/HT206167");
      # http://lists.apple.com/archives/security-announce/2016/Mar/msg00004.html
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6c87f79a");
      script_set_attribute(attribute:"solution", value:
    "Upgrade to Mac OS X version 10.11.4 or later.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
      script_set_cvss_temporal_vector("CVSS2#E:H/RL:OF/RC:C");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
      script_set_cvss3_temporal_vector("CVSS:3.0/E:H/RL:O/RC:C");
      script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-1761");
    
      script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
      script_set_attribute(attribute:"exploit_available", value:"true");
      script_set_attribute(attribute:"exploited_by_malware", value:"true");
      script_set_attribute(attribute:"exploit_framework_canvas", value:"true");
      script_set_attribute(attribute:"canvas_package", value:'CANVAS');
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2014/12/18");
      script_set_attribute(attribute:"patch_publication_date", value:"2016/03/21");
      script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/22");
    
      script_set_attribute(attribute:"plugin_type", value:"combined");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:apple:mac_os_x");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"MacOS X Local Security Checks");
    
      script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("ssh_get_info.nasl", "os_fingerprint.nasl");
      script_require_ports("Host/MacOSX/Version", "Host/OS");
    
      exit(0);
    }
    
    include("audit.inc");
    include("global_settings.inc");
    include("misc_func.inc");
    
    os = get_kb_item("Host/MacOSX/Version");
    if (!os)
    {
      os = get_kb_item_or_exit("Host/OS");
      if ("Mac OS X" >!< os)
        audit(AUDIT_OS_NOT, "Mac OS X");
    
      c = get_kb_item("Host/OS/Confidence");
      if (c <= 70)
        exit(1, "Cannot determine the host's OS with sufficient confidence.");
    }
    if (!os)
      audit(AUDIT_OS_NOT, "Mac OS X");
    
    match = eregmatch(pattern:"Mac OS X ([0-9]+(\.[0-9]+)+)", string:os);
    if (isnull(match)) exit(1, "Failed to parse the Mac OS X version ('" + os + "').");
    
    version = match[1];
    
    if (
      version !~ "^10\.11([^0-9]|$)"
    ) audit(AUDIT_OS_NOT, "Mac OS X 10.11 or later", "Mac OS X "+version);
    
    fix = "10.11.4";
    if (ver_compare(ver:version, fix:fix, strict:FALSE) == -1)
    {
      items = make_array("Installed version", version,
                         "Fixed version", fix
                        );
      order = make_list("Installed version", "Fixed version");
      report = report_items_str(report_items:items, ordered_fields:order);
    
      security_report_v4(port:0, extra:report, severity:SECURITY_HOLE);
      exit(0);
    
     }
    else
      audit(AUDIT_INST_VER_NOT_VULN, "Mac OS X", version);