Vulnerabilities > CVE-2016-1784 - Resource Exhaustion vulnerability in Apple Iphone OS

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
apple
CWE-400
nessus

Summary

The History implementation in WebKit in Apple iOS before 9.3, Safari before 9.1, and tvOS before 9.2 allows remote attackers to cause a denial of service (resource consumption and application crash) via a crafted web site.

Vulnerable Configurations

Part Description Count
OS
Apple
189
Application
Apple
145

Common Attack Pattern Enumeration and Classification (CAPEC)

  • XML Ping of the Death
    An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.
  • XML Entity Expansion
    An attacker submits an XML document to a target application where the XML document uses nested entity expansion to produce an excessively large output XML. XML allows the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.
  • Inducing Account Lockout
    An attacker leverages the security functionality of the system aimed at thwarting potential attacks to launch a denial of service attack against a legitimate system user. Many systems, for instance, implement a password throttling mechanism that locks an account after a certain number of incorrect log in attempts. An attacker can leverage this throttling mechanism to lock a legitimate user out of their own account. The weakness that is being leveraged by an attacker is the very security feature that has been put in place to counteract attacks.
  • Violating Implicit Assumptions Regarding XML Content (aka XML Denial of Service (XDoS))
    XML Denial of Service (XDoS) can be applied to any technology that utilizes XML data. This is, of course, most distributed systems technology including Java, .Net, databases, and so on. XDoS is most closely associated with web services, SOAP, and Rest, because remote service requesters can post malicious XML payloads to the service provider designed to exhaust the service provider's memory, CPU, and/or disk space. The main weakness in XDoS is that the service provider generally must inspect, parse, and validate the XML messages to determine routing, workflow, security considerations, and so on. It is exactly these inspection, parsing, and validation routines that XDoS targets. There are three primary attack vectors that XDoS can navigate Target CPU through recursion: attacker creates a recursive payload and sends to service provider Target memory through jumbo payloads: service provider uses DOM to parse XML. DOM creates in memory representation of XML document, but when document is very large (for example, north of 1 Gb) service provider host may exhaust memory trying to build memory objects. XML Ping of death: attack service provider with numerous small files that clog the system. All of the above attacks exploit the loosely coupled nature of web services, where the service provider has little to no control over the service requester and any messages the service requester sends.

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
);