CVE-2020-6481 in Chrome
Summary
by MITRE
Insufficient policy enforcement in URL formatting in Google Chrome prior to 83.0.4103.61 allowed a remote attacker to perform domain spoofing via a crafted domain name.
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Analysis
by VulDB Data Team • 05/06/2025
The vulnerability identified as CVE-2020-6481 represents a critical flaw in Google Chrome's handling of URL formatting and domain validation mechanisms. This issue stems from insufficient policy enforcement during the processing of web addresses, particularly when dealing with specially crafted domain names that can exploit the browser's rendering and validation logic. The vulnerability affects Chrome versions prior to 83.0.4103.61, creating a window of exposure where users could be deceived through maliciously constructed web addresses that appear legitimate but direct to malicious destinations.
The technical root cause of this vulnerability lies in Chrome's inadequate validation of domain names during URL parsing and display operations. When processing domain names that contain specific formatting sequences or Unicode characters, the browser fails to properly enforce its security policies that should prevent domain spoofing attacks. This weakness allows attackers to craft domain names that, when displayed in the browser's address bar or other UI elements, appear to belong to trusted entities while actually resolving to malicious servers. The flaw specifically manifests when Chrome's URL parser does not adequately sanitize or normalize domain names before presenting them to users, creating opportunities for attackers to exploit the browser's trust model.
The operational impact of this vulnerability extends beyond simple phishing attacks, as it fundamentally undermines user trust in the browser's security assurances. Attackers can leverage this flaw to create convincing domain spoofing scenarios where malicious websites appear to be legitimate services such as banking portals, social media platforms, or corporate intranets. Users who rely on Chrome's address bar for security verification may be misled into believing they are visiting trusted websites when they are actually interacting with malicious infrastructure. This creates significant risks for credential theft, data exfiltration, and other malicious activities that depend on user trust and perceived legitimacy of the visited domains.
Security researchers have classified this vulnerability under CWE-601, which specifically addresses URL redirector vulnerabilities and the improper handling of web addresses. The flaw aligns with ATT&CK technique T1566, which covers phishing attacks through malicious email or web content, and particularly relates to the domain spoofing and credential access phases of attack chains. Organizations and individual users who were running affected Chrome versions faced elevated risk of falling victim to sophisticated social engineering campaigns that exploited this browser-level weakness, making it a critical security concern for enterprises with mobile workforce or users who frequently access potentially malicious web content.
The remediation approach for this vulnerability required immediate patching of Chrome installations to version 83.0.4103.61 or later, which implemented enhanced URL parsing and validation logic. Security teams should have prioritized deployment of this update across all managed devices and encouraged users to update their browsers immediately. Additionally, organizations should have implemented network-level monitoring to detect and block suspicious domain patterns that could indicate exploitation attempts, while also conducting user awareness training to help identify potential spoofing attempts even when the browser itself is not vulnerable. The fix addressed the core issue by strengthening Chrome's domain name normalization and validation processes, ensuring that all domain names are properly sanitized before being displayed to users in the browser interface.