CVE-2008-6997 in Chrome
Summary
by MITRE
Google Chrome 0.2.149.27 allows user-assisted remote attackers to cause a denial of service (browser crash) via an IMG tag with a long src attribute, which triggers the crash when the victim performs an "Inspect Element" action.
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Analysis
by VulDB Data Team • 11/03/2024
The vulnerability described in CVE-2008-6997 represents a classic buffer overflow condition that affects Google Chrome version 0.2.149.27, demonstrating how seemingly benign HTML elements can be weaponized to disrupt browser operations. This issue specifically targets the browser's handling of image source attributes within HTML markup, where an attacker can craft an IMG tag with an excessively long src attribute value. The flaw operates under the principle that Chrome's rendering engine fails to properly validate or limit the length of URL strings before processing them during element inspection operations.
The technical mechanism behind this vulnerability stems from insufficient input validation within Chrome's DOM parsing and rendering components. When a user encounters an IMG tag with an abnormally long src attribute, the browser's internal string handling routines attempt to process this excessive data without proper bounds checking. This particular implementation flaw becomes exploitable when users perform the "Inspect Element" action, which triggers Chrome's developer tools to parse and display the element's properties, including the lengthy source attribute. The browser's failure to implement proper memory allocation limits for URL processing causes a stack overflow or heap corruption that results in immediate browser termination.
From an operational perspective, this vulnerability creates a significant denial of service risk for Chrome users, particularly in environments where browser stability is critical. The attack requires user interaction through the "Inspect Element" functionality, making it a user-assisted remote attack that cannot be automatically exploited without victim engagement. However, the ease with which an attacker can craft malicious web pages that trigger this condition makes it particularly concerning for web application security. The vulnerability directly impacts the availability of the browser service and can be used to disrupt user productivity or potentially serve as a stepping stone for more sophisticated attacks.
The security implications extend beyond simple service disruption, as this vulnerability demonstrates the importance of input validation in browser engines and highlights weaknesses in Chrome's handling of malformed HTML elements. This issue aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a failure in proper bounds checking within the browser's HTML processing pipeline. From an ATT&CK framework perspective, this vulnerability could be categorized under T1059 for command and scripting interpreter usage, as it involves manipulating browser rendering through HTML elements, and potentially T1499 for network denial of service attacks through browser exploitation.
Effective mitigation strategies for this vulnerability include implementing proper input validation mechanisms that limit the maximum length of URL attributes before processing them, as well as ensuring that browser rendering engines perform adequate bounds checking on all user-supplied data. Browser vendors should implement automatic truncation of excessively long URL strings and establish robust memory management practices to prevent buffer overflow conditions. Users can protect themselves by keeping their browsers updated, avoiding untrusted websites, and being cautious when performing inspection actions on unknown web content. The vulnerability also underscores the necessity of regular security audits of browser rendering engines and proper implementation of defensive programming practices to prevent similar issues in future browser versions.