CVE-2013-3192 in Internet Explorer
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Microsoft Internet Explorer 6 through 10 allows remote attackers to inject arbitrary web script or HTML via crafted character sequences with EUC-JP encoding, aka "EUC-JP Character Encoding Vulnerability."
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Analysis
by VulDB Data Team • 05/21/2021
The CVE-2013-3192 vulnerability represents a critical cross-site scripting flaw in Microsoft Internet Explorer versions 6 through 10 that exploits character encoding inconsistencies in the browser's handling of EUC-JP encoded content. This vulnerability falls under the CWE-79 category of Cross-Site Scripting, specifically manifesting as a weakness in input validation and output encoding. The flaw enables remote attackers to execute malicious scripts in the context of the victim's browser by crafting specially formatted character sequences that leverage the EUC-JP character encoding standard.
The technical mechanism behind this vulnerability involves Internet Explorer's inconsistent handling of EUC-JP encoded characters during the parsing process. When the browser encounters specific byte sequences within EUC-JP encoded content, it fails to properly sanitize or encode these characters before rendering them in the web page context. This parsing inconsistency creates a window where attacker-controlled data can bypass security mechanisms and execute unintended code within the victim's browser session. The vulnerability specifically targets the way IE processes multibyte character encodings and their interaction with the browser's rendering engine, making it particularly insidious as it can be triggered through seemingly benign web content.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform session hijacking, deface web applications, steal sensitive cookies, and conduct various malicious activities within the victim's browser context. The vulnerability affects a wide range of Internet Explorer versions, creating a substantial attack surface given the prevalence of these older browser versions in enterprise environments. Attackers can exploit this through various vectors including malicious web pages, email attachments, or compromised websites that serve EUC-JP encoded content containing malicious payloads. The attack requires no special privileges or user interaction beyond visiting a malicious website, making it particularly dangerous for widespread exploitation.
Organizations affected by this vulnerability should implement immediate mitigations including browser updates to the latest Internet Explorer versions, deployment of security patches from Microsoft, and implementation of proper input validation on web applications. Network-based mitigations such as web application firewalls and content filtering systems can help detect and block malicious EUC-JP encoded content. Additionally, security awareness training for users to avoid visiting untrusted websites and implementing strict browser security policies can reduce the risk of exploitation. The vulnerability demonstrates the importance of proper character encoding handling in web browsers and highlights the need for comprehensive input validation across all application layers. From an ATT&CK perspective, this vulnerability maps to technique T1059.001 for command and scripting interpreter and T1566 for phishing, as it enables attackers to deliver malicious payloads through web-based attack vectors. The vulnerability also underscores the critical need for maintaining up-to-date software and implementing defense-in-depth strategies to protect against legacy browser vulnerabilities that may remain unpatched in certain environments.