About the security content of watchOS 5.3

This document describes the security content of watchOS 5.3.

About Apple security updates

For our customers' protection, Apple doesn't disclose, discuss or confirm security issues until an investigation has taken place and patches or releases are available. Recent releases are listed on the Apple security updates page.

Apple security documents reference vulnerabilities by CVE-ID when possible.

For more information about security, see the Apple Product Security page.

watchOS 5.3

Bluetooth

Available for: Apple Watch Series 1 and later

Impact: An attacker in a privileged network position may be able to intercept Bluetooth traffic (Key Negotiation of Bluetooth – KNOB)

Description: An input validation issue existed in Bluetooth. This issue was addressed with improved input validation.

CVE-2019-9506: Daniele Antonioli of SUTD, Singapore, Dr. Nils Ole Tippenhauer of CISPA, Germany and Prof. Kasper Rasmussen of University of Oxford, England

The changes for this issue mitigate CVE-2020-10135.

Core Data

Available for: Apple Watch Series 1 and later

Impact: a remote attacker may be able to leak memory

Description: An out-of-bounds read was addressed with improved input validation.

CVE-2019-8646: natashenka of Google Project Zero

Core Data

Available for: Apple Watch Series 1 and later

Impact: A remote attacker may be able to cause arbitrary code execution

Description: A use after free issue was addressed with improved memory management.

CVE-2019-8647: Samuel Groß and natashenka of Google Project Zero

Core Data

Available for: Apple Watch Series 1 and later

Impact: A remote attacker may be able to cause unexpected application termination or arbitrary code execution

Description: A memory corruption issue was addressed with improved input validation.

CVE-2019-8660: Samuel Groß and natashenka of Google Project Zero

Digital Touch

Available for: Apple Watch Series 1 and later

Impact: a remote attacker may be able to leak memory

Description: An out-of-bounds read was addressed with improved input validation.

CVE-2019-8624: natashenka of Google Project Zero

FaceTime

Available for: Apple Watch Series 1 and later

Impact: A remote attacker may be able to cause arbitrary code execution

Description: A memory corruption issue was addressed with improved input validation.

CVE-2019-8648: Tao Huang and Tielei Wang of Team Pangu

Heimdal

Available for: Apple Watch Series 1 and later

Impact: An issue existed in Samba that may allow attackers to perform unauthorised actions by intercepting communications between services

Description: This issue was addressed with improved checks to prevent unauthorised actions.

CVE-2018-16860: Isaac Boukris and Andrew Bartlett of the Samba Team and Catalyst

Image Processing

Available for: Apple Watch Series 1 and later

Impact: Processing a maliciously crafted image may lead to a denial of service

Description: A denial-of-service issue was addressed with improved validation.

CVE-2019-8668: an anonymous researcher

Kernel

Available for: Apple Watch Series 1 and later

Impact: An application may be able to read restricted memory

Description: A validation issue was addressed with improved input sanitisation.

CVE-2019-8633: Zhuo Liang of Qihoo 360 Vulcan Team

libxslt

Available for: Apple Watch Series 1 and later

Impact: A remote attacker may be able to view sensitive information

Description: A stack overflow was addressed with improved input validation.

CVE-2019-13118: found by OSS-Fuzz

Messages

Available for: Apple Watch Series 1 and later

Impact: Users removed from an iMessage conversation may still be able to alter state

Description: This issue was addressed with improved checks.

CVE-2019-8659: Ryan Kontos (@ryanjkontos), Will Christensen of University of Oregon

Messages

Available for: Apple Watch Series 1 and later

Impact: A remote attacker may cause an unexpected application termination

Description: A denial-of-service issue was addressed with improved validation.

CVE-2019-8665: Michael Hernandez of XYZ Marketing

Quick Look

Available for: Apple Watch Series 1 and later

Impact: An attacker may be able to trigger a use-after-free in an application deserialising an untrusted NSDictionary

Description: This issue was addressed with improved checks.

CVE-2019-8662: natashenka and Samuel Groß of Google Project Zero

Siri

Available for: Apple Watch Series 1 and later

Impact: a remote attacker may be able to leak memory

Description: An out-of-bounds read was addressed with improved input validation.

CVE-2019-8646: natashenka of Google Project Zero

UIFoundation

Available for: Apple Watch Series 1 and later

Impact: Parsing a maliciously crafted office document may lead to an unexpected application termination or arbitrary code execution

Description: an out-of-bounds read was addressed with improved input validation.

CVE-2019-8657: riusksk of VulWar Corp working with Trend Micro's Zero Day Initiative

Wallet

Available for: Apple Watch Series 1 and later

Impact: A user may inadvertently complete an in-app purchase while on the lock screen

Description: the issue was addressed with improved UI handling.

CVE-2019-8682: Jeff Braswell (JeffBraswell.com)

WebKit

Available for: Apple Watch Series 1 and later

Impact: Processing maliciously crafted web content may lead to universal cross-site scripting

Description: A logic issue was addressed with improved state management.

CVE-2019-8658: akayn working with Trend Micro's Zero Day Initiative

WebKit

Available for: Apple Watch Series 1 and later

Impact: Processing maliciously crafted web content may lead to arbitrary code execution

Description: Multiple memory corruption issues were addressed with improved memory handling.

CVE-2019-8669: akayn working with Trend Micro's Zero Day Initiative

CVE-2019-8672: Samuel Groß of Google Project Zero

CVE-2019-8676: Soyeon Park and Wen Xu of SSLab at Georgia Tech

CVE-2019-8683: lokihardt of Google Project Zero

CVE-2019-8684: lokihardt of Google Project Zero

CVE-2019-8685: akayn, Dongzhuo Zhao working with ADLab of Venustech, Ken Wong (@wwkenwong) of VXRL, Anthony Lai (@darkfloyd1014) of VXRL and Eric Lung (@Khlung1) of VXRL

CVE-2019-8688: Insu Yun of SSLab at Georgia Tech

CVE-2019-8689: lokihardt of Google Project Zero

Additional recognition

MobileInstallation

We would like to acknowledge Dany Lisiansky (@DanyL931) for their assistance.