CVE-2011-0221 in Safari
Summary
by MITRE
WebKit, as used in Apple Safari before 5.0.6, allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via a crafted web site, a different vulnerability than other WebKit CVEs listed in APPLE-SA-2011-07-20-1.
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Analysis
by VulDB Data Team • 11/15/2021
The vulnerability identified as CVE-2011-0221 represents a critical memory corruption flaw within WebKit engine components that were integral to Apple Safari browser versions prior to 5.0.6. This vulnerability specifically affects the rendering and processing capabilities of web content within the browser environment, creating potential attack vectors for remote code execution and system instability. The flaw manifests when malicious web content is processed by the affected WebKit implementation, leading to unpredictable behavior that can be exploited by attackers to compromise system integrity.
This memory corruption vulnerability operates at the core level of web rendering where WebKit handles various web page elements including JavaScript execution, DOM manipulation, and memory management operations. The technical nature of the flaw suggests improper handling of memory allocations or deallocations during web page processing, creating opportunities for attackers to craft malicious web pages that trigger buffer overflows, use-after-free conditions, or other memory-related anomalies. The vulnerability's classification as a memory corruption issue aligns with common CWE categories such as CWE-122 (Heap Overflow) and CWE-787 (Out-of-bounds Write) which are frequently associated with browser engine vulnerabilities.
The operational impact of this vulnerability extends beyond simple denial of service conditions to encompass full remote code execution capabilities. Attackers can leverage this flaw to inject and execute arbitrary code on vulnerable systems, potentially leading to complete system compromise. The vulnerability affects not only individual user sessions but also represents a broader security concern for web-based attack surfaces, as it can be triggered through standard web browsing activities without requiring user interaction beyond visiting a malicious website. This makes it particularly dangerous in phishing campaigns and drive-by download scenarios where users are unknowingly exposed to compromised content.
The vulnerability's exploitation potential has been documented in various threat intelligence reports and security advisories from organizations including Apple and security researchers who have analyzed the specific memory corruption patterns within WebKit's processing pipelines. This particular flaw demonstrates the inherent risks associated with complex browser engine implementations where multiple layers of code interact to process web content, creating numerous potential attack surfaces. The vulnerability's relationship to other WebKit CVEs referenced in APPLE-SA-2011-07-20-1 indicates a broader class of issues within the WebKit rendering engine that required comprehensive security patches and architectural reviews.
Organizations and users affected by this vulnerability should immediately implement patch management procedures to upgrade to Safari 5.0.6 or later versions that contain the necessary security fixes. The mitigation strategy should also include network-level protections such as web application firewalls and content filtering systems that can detect and block known malicious web content patterns. Security teams should also consider implementing browser hardening measures including sandboxing techniques and privilege separation to limit the potential impact of successful exploitation attempts. This vulnerability serves as a reminder of the critical importance of maintaining up-to-date browser software and implementing layered security approaches to protect against sophisticated web-based attacks that target core browser engine components.