CVE-2020-9947 in Safari
Summary
by MITRE • 12/09/2020
A use after free issue was addressed with improved memory management. This issue is fixed in watchOS 7.0, iOS 14.0 and iPadOS 14.0, iTunes for Windows 12.10.9, iCloud for Windows 11.5, tvOS 14.0, Safari 14.0. Processing maliciously crafted web content may lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 07/09/2025
The vulnerability identified as CVE-2020-9947 represents a critical use-after-free flaw that emerged within Apple's ecosystem, specifically affecting multiple operating systems and applications including iOS, watchOS, tvOS, and various desktop utilities. This memory safety issue stems from improper handling of memory allocation and deallocation processes, creating opportunities for malicious actors to exploit the system's memory management mechanisms. The vulnerability manifests when the system processes maliciously crafted web content, potentially allowing attackers to execute arbitrary code on affected devices. Such flaws are particularly dangerous because they can be triggered through seemingly benign web browsing activities, making them difficult to detect and prevent through traditional security measures.
The technical implementation of this vulnerability aligns with common patterns found in memory corruption issues classified under CWE-416, which specifically addresses use-after-free conditions where program code attempts to access memory after it has been freed. The exploit scenario involves attackers crafting specially designed web content that, when rendered by affected browsers or web views, triggers the flawed memory management code path. This allows attackers to manipulate the freed memory location and potentially overwrite critical program data or function pointers, leading to complete system compromise. The issue affects Apple's Safari browser and embedded web views across multiple platforms, making it a widespread concern that spans from mobile devices to desktop environments.
The operational impact of CVE-2020-9947 extends beyond simple privilege escalation, as it provides attackers with the capability to execute arbitrary code remotely through web-based attacks. This vulnerability directly maps to ATT&CK technique T1203, which involves exploitation of web browsers for code execution, and T1059, covering command and scripting interpreter usage. The attack surface includes any user interaction with malicious websites, making it particularly concerning for enterprise environments where users frequently access untrusted web content. The vulnerability's presence in critical applications like Safari, iTunes, and iCloud for Windows creates multiple potential entry points for adversaries to establish persistent access to target systems.
Apple's remediation efforts addressed this vulnerability through enhanced memory management protocols implemented in iOS 14.0, watchOS 7.0, tvOS 14.0, and updated versions of iTunes and iCloud for Windows. The fixes likely involved implementing stricter memory deallocation checks, adding additional validation mechanisms before memory access, and improving the overall garbage collection processes within the affected applications. Organizations should prioritize immediate deployment of these updates across all affected systems, as the vulnerability's exploitation potential makes it a high-priority security concern. Security teams should also implement network monitoring to detect potential exploitation attempts and consider deploying web application firewalls to mitigate the risk of malicious content reaching end-user systems. The vulnerability demonstrates the critical importance of maintaining up-to-date security patches and the potential consequences of failing to address memory safety issues in widely used applications and operating systems.