CVE-2010-0047 in Safari
Summary
by MITRE
Use-after-free vulnerability in WebKit in Apple Safari before 4.0.5 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via vectors related to "HTML object element fallback content."
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Analysis
by VulDB Data Team • 05/02/2026
The vulnerability identified as CVE-2010-0047 represents a critical use-after-free flaw within the WebKit rendering engine that powers Apple Safari browsers. This issue affects Safari versions prior to 4.0.5 and demonstrates a fundamental memory management error that can be exploited remotely by attackers to gain unauthorized code execution or cause application instability. The vulnerability specifically manifests when processing HTML object elements that contain fallback content, creating a scenario where freed memory locations are accessed after they have been deallocated by the browser's memory management system.
The technical root cause of this vulnerability stems from improper memory handling within the WebKit engine's object element processing logic. When Safari encounters HTML content with object elements that include fallback content, the browser allocates memory for these elements and subsequently frees it during normal operation. However, under certain conditions related to how the fallback content is rendered, the application attempts to access memory locations that have already been freed, creating a use-after-free condition. This memory corruption scenario occurs because the code does not properly validate that referenced memory remains valid before accessing it, allowing attackers to manipulate the freed memory through carefully crafted HTML payloads.
The operational impact of this vulnerability extends beyond simple application crashes to encompass full remote code execution capabilities. Attackers can leverage this flaw by hosting malicious web content that triggers the vulnerable code path when users browse to compromised websites. The use-after-free condition can be exploited to overwrite critical memory locations, potentially allowing attackers to inject and execute arbitrary code with the privileges of the browser process. This represents a severe security risk as it enables attackers to compromise user systems without requiring local access or user interaction beyond visiting a malicious website. The vulnerability's classification aligns with CWE-416, which specifically addresses use-after-free conditions in memory management.
From an adversarial perspective, this vulnerability demonstrates the sophisticated nature of modern browser exploits that target rendering engine components. Security researchers have documented similar patterns in the ATT&CK framework where adversaries leverage memory corruption vulnerabilities to establish persistent access or escalate privileges within compromised systems. The vulnerability's remote exploitability makes it particularly dangerous in phishing campaigns or malicious website deployments where users can be unknowingly exposed to attack vectors through routine web browsing activities. Organizations implementing security controls must recognize that such vulnerabilities often require immediate patching due to their high severity and active exploitation in the wild.
Mitigation strategies for CVE-2010-0047 focus primarily on applying the official security patches released by Apple, specifically upgrading to Safari 4.0.5 or later versions. System administrators should implement comprehensive patch management policies that ensure timely deployment of security updates across all affected browser installations. Additionally, network-based protections such as web application firewalls and content filtering systems can provide additional defense-in-depth layers to block known malicious content. Browser hardening techniques including sandboxing and privilege separation can help limit the potential impact of successful exploitation attempts, while regular security assessments and penetration testing can help identify similar vulnerabilities in other browser components or web applications that may be susceptible to similar memory corruption flaws.