CVE-2018-4214

Vulnerability

CVE-2018-4214 is a memory corruption vulnerability in the WebKit component of certain Apple products. The issue exists in iOS before version 11.4, Safari before version 11.1.1, iCloud before version 7.5 on Windows, iTunes before version 12.7.5 on Windows, tvOS before version 11.4, and watchOS before version 4.3.1. The vulnerability can be triggered when WebKit processes maliciously crafted web content, leading to memory corruption.

Exploitation

To exploit this vulnerability, an attacker needs to host a crafted website that, when visited by a user on an affected device, triggers the memory corruption in WebKit. No special network position or authentication is required beyond delivering the web content to the user. The exact exploitation steps involve the attacker creating or injecting specific web content that exploits the memory corruption flaw.

Impact

Successful exploitation could allow a remote attacker to cause a denial of service, specifically a Safari crash, due to memory corruption. The official description also mentions "possibly have unspecified other impact," but given the out-of-bounds read nature described in the Apple advisory for related products [4], arbitrary code execution may also be possible [4]. The attacker could achieve a denial of service or potentially gain the ability to execute arbitrary code on the affected system.

Mitigation

Apple released fixes for CVE-2018-4214 on May 29, 2018, as part of iOS 11.4 [1], Safari 11.1.1 [1], tvOS 11.4 [2], watchOS 4.3.1 [3], iCloud 7.5 for Windows [4], and iTunes 12.7.5 for Windows [4]. Users should update to these or later versions to mitigate the vulnerability. No workarounds are listed in the available references.