CVE-2011-3102 in iOS
Summary
by MITRE
Off-by-one error in libxml2, as used in Google Chrome before 19.0.1084.46 and other products, allows remote attackers to cause a denial of service (out-of-bounds write) or possibly have unspecified other impact via unknown vectors.
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Analysis
by VulDB Data Team • 05/25/2021
The vulnerability identified as CVE-2011-3102 represents a critical off-by-one error within the libxml2 library implementation that affects Google Chrome versions prior to 19.0.1084.46 and numerous other software products relying on this XML parsing library. This type of flaw falls under the CWE-129 category of Improper Validation of Array Index, where the software fails to properly validate array indices before accessing memory locations. The issue manifests when libxml2 processes malformed XML content that triggers an out-of-bounds write condition, potentially allowing remote attackers to execute arbitrary code or cause system instability through carefully crafted input data.
The technical exploitation of this vulnerability occurs during XML parsing operations where the libxml2 library incorrectly handles boundary conditions in memory allocation and array access patterns. When Chrome or other affected applications process malformed XML documents, the parser fails to validate array indices properly, leading to memory corruption that can result in denial of service conditions or more severe consequences including arbitrary code execution. This vulnerability operates at the intersection of software security and memory safety, specifically targeting the XML processing pipeline that is fundamental to web browsers and many enterprise applications. The out-of-bounds write condition creates opportunities for attackers to manipulate memory layout and potentially execute malicious code within the application context.
From an operational perspective, this vulnerability presents significant risk to organizations relying on web browsers and XML processing capabilities, as it can be exploited through web-based attacks without requiring user interaction. The impact extends beyond simple denial of service to potentially allow full system compromise, particularly when combined with other exploitation techniques or when the vulnerable applications run with elevated privileges. The vulnerability affects not only Google Chrome but also numerous other software products including web servers, content management systems, and enterprise applications that utilize libxml2 for XML processing. Organizations should consider the ATT&CK framework's T1203 - Exploitation for Client Execution when evaluating potential attack vectors, as this vulnerability enables remote code execution through web-based delivery mechanisms.
Mitigation strategies should prioritize immediate patching of affected software versions and implementation of XML input validation controls. Organizations should deploy web application firewalls and content filtering solutions to block malformed XML content before it reaches vulnerable applications. The principle of least privilege should be enforced by running affected applications with minimal required permissions, and regular security assessments should include testing for similar memory corruption vulnerabilities. Additionally, implementing memory protection mechanisms such as stack canaries, address space layout randomization, and data execution prevention can provide defense-in-depth against exploitation attempts. Regular monitoring of security advisories and vulnerability assessments should be maintained to identify and remediate similar issues across the organization's software portfolio.