CVE-2016-4677 in tvOS
Summary
by MITRE
An issue was discovered in certain Apple products. iOS before 10.1 is affected. Safari before 10.0.1 is affected. tvOS before 10.0.1 is affected. The issue involves the "WebKit" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site.
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Analysis
by VulDB Data Team • 09/28/2022
The vulnerability identified as CVE-2016-4677 represents a critical memory corruption flaw within Apple's WebKit rendering engine that affected multiple Apple operating systems including iOS versions prior to 10.1 Safari versions before 10.0.1 and tvOS versions before 10.0.1. This weakness resides in the core web browsing component responsible for rendering web content and processing JavaScript commands which makes it particularly dangerous given the widespread use of web browsers. The vulnerability stems from improper memory management during web page processing which creates opportunities for attackers to manipulate memory structures through maliciously crafted web content.
The technical exploitation of this vulnerability occurs when a remote attacker crafts a specific web page that triggers memory corruption within the WebKit engine. This memory corruption can manifest in two primary ways: arbitrary code execution allowing attackers to run malicious software on affected devices or denial of service conditions causing applications to crash and become unresponsive. The flaw typically involves buffer overflows or use-after-free conditions where the WebKit engine improperly handles memory allocation and deallocation during web page rendering processes. Attackers can leverage this vulnerability by hosting malicious content on compromised websites or through phishing attacks that direct users to exploit the memory corruption through standard web browsing activities.
The operational impact of CVE-2016-4677 extends beyond simple application crashes as it provides attackers with potential persistence mechanisms and access to sensitive device functionality. When successful, the memory corruption allows attackers to execute arbitrary code with the privileges of the affected application, potentially leading to complete device compromise. The vulnerability affects all affected Apple platforms, making it particularly concerning for users who may encounter malicious content across different device types. The remote nature of the attack means that users need only visit a compromised website to be vulnerable, eliminating the need for physical access or additional social engineering elements.
Mitigation strategies for this vulnerability require immediate system updates to the latest available versions of affected Apple operating systems. Apple released security updates for iOS 10.1 Safari 10.0.1 and tvOS 10.0.1 that address the memory corruption issues within WebKit. Organizations should implement comprehensive patch management processes to ensure all affected devices receive updates promptly. Network administrators can deploy web filtering solutions and browser security extensions to reduce exposure to malicious websites, while users should avoid visiting untrusted websites and maintain updated security software. The vulnerability aligns with CWE-125 Out-of-bounds Read and CWE-787 Out-of-bounds Write categories from the Common Weakness Enumeration catalog, representing memory safety issues that frequently appear in browser engine implementations. From the ATT&CK framework perspective, this vulnerability maps to T1059 Command and Scripting Interpreter and T1203 Exploitation for Client Execution techniques, demonstrating how memory corruption flaws can be leveraged for remote code execution attacks.