CVE-2011-2833 in iOS
Summary
by MITRE
WebKit, as used in Apple iOS before 5.1 and iTunes before 10.6, 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-2012-03-07-1 and APPLE-SA-2012-03-07-2.
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Analysis
by VulDB Data Team • 03/21/2021
The vulnerability identified as CVE-2011-2833 represents a critical memory corruption flaw within WebKit engine implementations used in Apple iOS versions prior to 5.1 and iTunes versions before 10.6. This vulnerability resides in the core rendering engine that powers web browsing capabilities across Apple's ecosystem, making it a prime target for remote exploitation. The flaw specifically manifests when processing maliciously crafted web content that triggers improper memory handling during web page rendering operations. Such vulnerabilities are particularly dangerous because they can be exploited through standard web browsing activities without requiring any special privileges or user interaction beyond visiting a compromised website.
The technical nature of this vulnerability involves improper memory management during the processing of web content, leading to memory corruption that can be leveraged by remote attackers to execute arbitrary code on affected systems. This type of flaw typically occurs when the WebKit engine fails to properly validate or sanitize input data from web pages, resulting in buffer overflows, use-after-free conditions, or other memory corruption patterns. The vulnerability's classification aligns with CWE-121, which describes heap-based buffer overflow conditions, and CWE-122, which covers buffer overflow vulnerabilities in heap memory. Attackers can craft malicious web pages that, when loaded in the vulnerable WebKit engine, cause the memory layout to become corrupted, potentially allowing execution of malicious code with the privileges of the affected application.
The operational impact of this vulnerability extends beyond simple application crashes, as it provides attackers with the capability to achieve remote code execution on targeted devices. This means that users visiting malicious websites could have their iOS devices or iTunes installations compromised without any explicit user action beyond normal web browsing. The vulnerability affects not only mobile devices but also desktop computing environments where iTunes was used, creating a wide attack surface. The fact that this vulnerability was distinct from other WebKit CVEs mentioned in the referenced Apple security advisories indicates it represents a unique memory corruption pattern that required specific mitigation approaches. The potential for denial of service combined with remote code execution makes this vulnerability particularly concerning for enterprise and individual users alike.
Mitigation strategies for CVE-2011-2833 primarily involve updating to patched versions of Apple iOS and iTunes, specifically iOS 5.1 and iTunes 10.6 or later. Organizations should implement immediate patch management procedures to ensure all affected systems receive the necessary updates. Network-level protections such as web content filtering and sandboxing measures can provide additional defense in depth, though they cannot replace proper patching. The vulnerability demonstrates the importance of maintaining up-to-date software across all platforms, as the attack surface expands with each unpatched vulnerability. Security teams should monitor for related vulnerabilities and implement comprehensive vulnerability management programs that address both known and emerging threats in web browser engines. This vulnerability also highlights the need for regular security assessments of web-based applications and the importance of following secure coding practices to prevent similar memory corruption issues in the future.