CVE-2015-0021 in Internet Explorer
Summary
by MITRE
Microsoft Internet Explorer 6 through 10 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted web site, aka "Internet Explorer Memory Corruption Vulnerability."
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Analysis
by VulDB Data Team • 03/09/2022
The vulnerability identified as CVE-2015-0021 represents a critical memory corruption flaw affecting Microsoft Internet Explorer versions 6 through 10. This vulnerability resides within the browser's handling of memory operations during web page rendering, creating a pathway for malicious actors to execute arbitrary code on affected systems or induce denial of service conditions. The flaw specifically manifests when Internet Explorer processes crafted web content that triggers improper memory management behaviors, leading to unpredictable system states that adversaries can exploit for malicious purposes.
From a technical perspective, this vulnerability operates through memory corruption mechanisms that allow attackers to manipulate heap memory structures within the browser process. The flaw typically occurs when Internet Explorer encounters specially crafted HTML elements or JavaScript code that causes memory allocation errors, buffer overflows, or use-after-free conditions. These memory corruption issues arise from inadequate input validation and memory management routines within the browser's rendering engine, particularly affecting the scripting and object model components that handle dynamic web content execution. The vulnerability's classification aligns with CWE-121, which addresses stack-based buffer overflow conditions, and CWE-125, which covers out-of-bounds read errors.
The operational impact of CVE-2015-0021 extends beyond simple code execution to encompass significant security risks for enterprise environments. Attackers leveraging this vulnerability can gain unauthorized access to systems, escalate privileges, and potentially establish persistent backdoors through the execution of malicious payloads. The memory corruption nature makes detection challenging as the exploitation may appear as random crashes or unexpected behavior before full compromise occurs. Organizations running affected Internet Explorer versions face elevated risk during web browsing activities, particularly when users access untrusted websites or encounter phishing content that triggers the vulnerable code paths. The vulnerability also enables denial of service attacks that can disrupt business operations by causing browser crashes or system instability.
Mitigation strategies for this vulnerability require immediate patch application through Microsoft's security updates, as the primary fix involves correcting the memory management routines within Internet Explorer's core components. Organizations should implement browser hardening measures including disabling unnecessary browser features, implementing content security policies, and restricting access to potentially malicious websites through web filtering solutions. Network-based protections such as intrusion detection systems and web application firewalls can help detect exploitation attempts, while endpoint protection solutions should be configured to monitor for suspicious memory access patterns. Additionally, security teams should consider implementing browser isolation techniques and encouraging user education regarding safe browsing practices to reduce exposure risk. The vulnerability's exploitation aligns with ATT&CK technique T1203, which covers exploitation for client execution, and T1059, covering command and scripting interpreter usage, making comprehensive defense-in-depth strategies essential for effective protection.