About the security content of watchOS 4.2

This document describes the security content of watchOS 4.2.

About Apple security updates

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

For more information about security, see the Apple Product Security page. You can encrypt communications with Apple using the Apple Product Security PGP Key.

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

watchOS 4.2

Auto Unlock

Available for: All Apple Watch models

Impact: An application may be able to gain elevated privileges

Description: A race condition was addressed with additional validation.

CVE-2017-13905: Samuel Groß (@5aelo)

CFNetwork Session

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with system privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-7172: Richard Zhu (fluorescence) working with Trend Micro's Zero Day Initiative

CoreAnimation

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with elevated privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-7171: 360 Security working with Trend Micro's Zero Day Initiative, and Tencent Keen Security Lab (@keen_lab) working with Trend Micro's Zero Day Initiative

CoreFoundation

Available for: All Apple Watch models

Impact: An application may be able to gain elevated privileges

Description: A race condition was addressed with additional validation.

CVE-2017-7151: Samuel Groß (@5aelo)

IOKit

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with kernel privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-7162: Tencent Keen Security Lab (@keen_lab) working with Trend Micro's Zero Day Initiative

IOSurface

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with kernel privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-13861: Ian Beer of Google Project Zero

Kernel

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with kernel privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-13904: Kevin Backhouse of Semmle Ltd.

Kernel

Available for: All Apple Watch models

Impact: A local user may be able to cause unexpected system termination or read kernel memory

Description: An input validation issue existed in the kernel. This issue was addressed through improved input validation.

CVE-2017-7154: Jann Horn of Google Project Zero

Kernel

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with kernel privileges

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-13862: Apple

CVE-2017-13867: Ian Beer of Google Project Zero

CVE-2017-13876: Ian Beer of Google Project Zero

Kernel

Available for: All Apple Watch models

Impact: An application may be able to read restricted memory

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

CVE-2017-7173: Brandon Azad

Kernel

Available for: All Apple Watch models

Impact: An application may be able to read restricted memory

Description: A type confusion issue was addressed with improved memory handling.

CVE-2017-13855: Jann Horn of Google Project Zero

Kernel

Available for: All Apple Watch models

Impact: An application may be able to read restricted memory

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

CVE-2017-13865: Ian Beer of Google Project Zero

CVE-2017-13868: Brandon Azad

CVE-2017-13869: Jann Horn of Google Project Zero

Kernel

Available for: All Apple Watch models

Impact: An application may be able to execute arbitrary code with kernel privilege

Description: A memory corruption issue was addressed with improved memory handling.

CVE-2017-13880: Apple

WebKit

Available for: All Apple Watch models

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

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

CVE-2017-7165: 360 Security working with Trend Micro's Zero Day Initiative

WebKit

Available for: All Apple Watch models

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

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

CVE-2017-13884: 360 Security working with Trend Micro's Zero Day Initiative

WebKit

Available for: All Apple Watch models

Impact: Visiting a malicious website may lead to user interface spoofing

Description: Redirect responses to 401 Unauthorized may allow a malicious website to incorrectly display the lock icon on mixed content. This issue was addressed through improved URL display logic.

CVE-2017-7153: Jerry Decime

Wi-Fi

Available for: Apple Watch (1st Generation) and Apple Watch Series 3

Impact: An attacker in Wi-Fi range may force nonce reuse in WPA multicast/GTK clients (Key Reinstallation Attacks - KRACK)

Description: A logic issue existed in the handling of state transitions. This was addressed with improved state management.

CVE-2017-13080: Mathy Vanhoef of the imec-DistriNet group at KU Leuven

No impact

watchOS 4.2 is not impacted by the following issue:

Kernel

Impact: An application may be able to read kernel memory (Meltdown)

Description: Systems with microprocessors utilizing speculative execution and indirect branch prediction may allow unauthorized disclosure of information to an attacker with local user access via a side-channel analysis of the data cache.

CVE-2017-5754: Jann Horn of Google Project Zero; Moritz Lipp of Graz University of Technology; Michael Schwarz of Graz University of Technology; Daniel Gruss of Graz University of Technology; Thomas Prescher of Cyberus Technology GmbH; Werner Haas of Cyberus Technology GmbH; Stefan Mangard of Graz University of Technology; Paul Kocher; Daniel Genkin of University of Pennsylvania and University of Maryland; Yuval Yarom of University of Adelaide and Data61; and Mike Hamburg of Rambus (Cryptography Research Division)