CVE-2020-6409 in Chrome
Summary
by MITRE
Inappropriate implementation in Omnibox in Google Chrome prior to 80.0.3987.87 allowed a remote attacker who convinced the user to enter a URI to bypass navigation restrictions via a crafted domain name.
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Analysis
by VulDB Data Team • 05/10/2025
The vulnerability identified as CVE-2020-6409 represents a critical flaw in Google Chrome's Omnibox implementation that fundamentally compromised the browser's navigation security model. This issue existed in Chrome versions prior to 80.0.3987.87 and allowed remote attackers to bypass intended navigation restrictions through carefully crafted domain names. The flaw specifically targeted the browser's address bar validation mechanisms, which are critical components responsible for determining whether user-entered URIs should be processed for navigation. The vulnerability exploited the way Chrome interpreted and validated domain names entered by users, creating a pathway for malicious actors to circumvent security controls designed to prevent unauthorized navigation attempts.
The technical implementation flaw resides in how Chrome's Omnibox component handles domain name parsing and validation during user input processing. When users entered crafted domain names, the browser's validation logic failed to properly sanitize or restrict the input, allowing attackers to construct domain names that would bypass the intended security boundaries. This type of vulnerability falls under CWE-20, "Improper Input Validation," where the system fails to properly validate or sanitize user-provided input before processing it. The flaw essentially created a bypass mechanism where malicious domain names could be interpreted in ways that circumvented Chrome's built-in navigation restrictions, potentially allowing users to be redirected to malicious sites without proper security checks.
The operational impact of this vulnerability extends beyond simple navigation bypass, as it represents a significant threat to user security and privacy. Attackers could leverage this flaw to trick users into entering seemingly benign domain names that would actually redirect them to malicious destinations. The vulnerability was particularly dangerous because it required no special privileges or complex exploitation techniques - it only needed to convince a user to enter a crafted URI. This made it highly effective as a social engineering vector, as users would typically trust the browser's address bar and navigation functionality. The attack could potentially lead to phishing attacks, malware delivery, or other malicious activities that would otherwise be blocked by Chrome's navigation restrictions.
Mitigation strategies for this vulnerability primarily focused on updating to Chrome version 80.0.3987.87 or later, which contained the necessary patches to fix the Omnibox validation logic. Organizations should have implemented immediate patch management procedures to ensure all affected systems were updated promptly. Additional defensive measures included enhanced user education about the risks of entering unfamiliar domain names and implementing network-level controls to monitor and block suspicious navigation attempts. From an ATT&CK framework perspective, this vulnerability aligns with techniques such as T1059.001 "Command and Scripting Interpreter: PowerShell" and T1566 "Phishing" as it could enable more sophisticated phishing attacks by bypassing browser security controls. The vulnerability also demonstrates the importance of input validation in web browsers and highlights how seemingly minor implementation flaws in user interface components can have significant security implications across the entire browser ecosystem.