Vulnerabilities > CVE-2018-4124 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Apple products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
An issue was discovered in certain Apple products. iOS before 11.2.6 is affected. macOS before 10.13.3 Supplemental Update is affected. tvOS before 11.2.6 is affected. watchOS before 4.2.3 is affected. The issue involves the "CoreText" component. It allows remote attackers to cause a denial of service (memory corruption and system crash) or possibly have unspecified other impact via a crafted string containing a certain Telugu character.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
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 family Misc. NASL id APPLETV_11_2_6.NASL description According to its banner, the version of Apple TV on the remote device is prior to 11.2.6. It is, therefore, affected by a memory corruption vulnerability as described in the HT208536 security advisory. Note that only 4th and 5th generation models are affected by these vulnerabilities. last seen 2020-06-01 modified 2020-06-02 plugin id 106974 published 2018-02-23 reporter This script is Copyright (C) 2004-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/106974 title Apple TV < 11.2.6 Telugu Character Handling Remote Memory Corruption Vulnerability code # # (C) Tenable Network Security, Inc. # include("compat.inc"); if (description) { script_id(106974); script_version("1.6"); script_cvs_date("Date: 2019/02/26 4:50:08"); script_cve_id("CVE-2018-4124"); script_bugtraq_id(103066); script_xref(name:"APPLE-SA", value:"APPLE-SA-2018-02-19-3"); script_name(english:"Apple TV < 11.2.6 Telugu Character Handling Remote Memory Corruption Vulnerability"); script_summary(english:"Checks the build number."); script_set_attribute(attribute:"synopsis", value: "The remote Apple TV device is affected by a memory corruption vulnerability."); script_set_attribute(attribute:"description", value: "According to its banner, the version of Apple TV on the remote device is prior to 11.2.6. It is, therefore, affected by a memory corruption vulnerability as described in the HT208536 security advisory. Note that only 4th and 5th generation models are affected by these vulnerabilities."); script_set_attribute(attribute:"see_also", value:"https://support.apple.com/en-us/HT208536"); script_set_attribute(attribute:"solution", value: "Upgrade to Apple TV version 11.2.6 or later. Note that this update is only available for 4th and 5th generation models."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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: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-2018-4124"); 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:"2018/02/14"); script_set_attribute(attribute:"patch_publication_date", value:"2018/02/19"); script_set_attribute(attribute:"plugin_publication_date", value:"2018/02/23"); 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) 2004-2019 and is owned by Tenable, Inc. or an Affiliate thereof."); script_dependencies("appletv_version.nasl"); script_require_keys("AppleTV/Version", "AppleTV/Model", "AppleTV/URL", "AppleTV/Port"); script_require_ports("Services/www", 7000); exit(0); } include("audit.inc"); include("appletv_func.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.'); # https://en.wikipedia.org/wiki/TvOS # 4th gen model "5,3" and 5th gen model "6,2" share same build fixed_build = "15K600"; tvos_ver = '11'; # determine gen from the model gen = APPLETV_MODEL_GEN[model]; appletv_check_version( build : build, fix : fixed_build, affected_gen : make_list(4, 5), fix_tvos_ver : tvos_ver, model : model, gen : gen, port : port, url : url, severity : SECURITY_HOLE );
NASL family MacOS X Local Security Checks NASL id MACOSX_10_13_3_SU1.NASL description The remote host is running a version of macOS 10.13.3 that is missing the macOS 10.13.3 Supplemental Update. This update fixes an input- validation flaw, which allows an attacker to cause memory corruption leading to application crashes and potentially to arbitrary code execution. last seen 2020-06-01 modified 2020-06-02 plugin id 107071 published 2018-02-28 reporter This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/107071 title macOS 10.13.3 Supplemental Update code #TRUSTED 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 # # (C) Tenable Network Security, Inc. # include("compat.inc"); if (description) { script_id(107071); script_version("1.6"); script_cvs_date("Date: 2019/11/08"); script_cve_id("CVE-2018-4124"); script_bugtraq_id(103066); script_xref(name:"APPLE-SA", value:"APPLE-SA-2018-02-19-2"); script_name(english:"macOS 10.13.3 Supplemental Update"); script_summary(english:"Check the version of Mac OS X / macOS."); script_set_attribute(attribute:"synopsis", value: "The remote host is missing a macOS security update that fixes an input-validation vulnerability."); script_set_attribute(attribute:"description", value: "The remote host is running a version of macOS 10.13.3 that is missing the macOS 10.13.3 Supplemental Update. This update fixes an input- validation flaw, which allows an attacker to cause memory corruption leading to application crashes and potentially to arbitrary code execution."); script_set_attribute(attribute:"see_also", value:"https://support.apple.com/en-us/HT208535"); # https://lists.apple.com/archives/security-announce/2018/Feb/msg00001.html script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?866048f5"); script_set_attribute(attribute:"solution", value: "Install the macOS 10.13.3 Supplemental Update."); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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: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-2018-4124"); script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available"); script_set_attribute(attribute:"vuln_publication_date", value:"2018/02/19"); script_set_attribute(attribute:"patch_publication_date", value:"2018/02/19"); script_set_attribute(attribute:"plugin_publication_date", value:"2018/02/28"); 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) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof."); script_dependencies("ssh_get_info.nasl"); script_require_keys("Host/local_checks_enabled", "Host/MacOSX/Version"); exit(0); } include("audit.inc"); include("global_settings.inc"); include("misc_func.inc"); include("ssh_func.inc"); include("macosx_func.inc"); if(sshlib::get_support_level() >= sshlib::SSH_LIB_SUPPORTS_COMMANDS) enable_ssh_wrappers(); else disable_ssh_wrappers(); if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED); os = get_kb_item("Host/MacOSX/Version"); if (!os) audit(AUDIT_OS_NOT, "Mac OS X / macOS"); if (!preg(pattern:"Mac OS X 10\.13\.3([^0-9]|$)", string:os)) audit(AUDIT_OS_NOT, "macOS 10.13.3"); # Get the product build version. plist = "/System/Library/CoreServices/SystemVersion.plist"; cmd = 'plutil -convert xml1 -o - \'' + plist + '\' | ' + 'grep -A 1 ProductBuildVersion | ' + 'tail -n 1 | ' + 'sed \'s/.*string>\\(.*\\)<\\/string>.*/\\1/g\''; build = exec_cmd(cmd:cmd); if ( !strlen(build) || build !~ "^17D[0-9]+$" ) exit(1, "Failed to extract the ProductBuildVersion from '"+plist+"'."); if (build =~ "^17D([0-9]|[0-9][0-9]|10[01])$") { report = '\n Product version : ' + os + '\n Installed product build version : ' + build + '\n Fixed product build version : 17D102' + '\n'; security_report_v4(port:0, severity:SECURITY_HOLE, extra:report); } else exit(0, "The host has product build version "+build+" and is not affected.");
References
- http://www.securitytracker.com/id/1040396
- http://www.securitytracker.com/id/1040396
- https://nakedsecurity.sophos.com/2018/02/20/apple-fixes-that-1-character-to-crash-your-mac-and-iphone-bug/
- https://nakedsecurity.sophos.com/2018/02/20/apple-fixes-that-1-character-to-crash-your-mac-and-iphone-bug/
- https://support.apple.com/HT208534
- https://support.apple.com/HT208534
- https://support.apple.com/HT208535
- https://support.apple.com/HT208535
- https://support.apple.com/HT208536
- https://support.apple.com/HT208536
- https://support.apple.com/HT208537
- https://support.apple.com/HT208537