CVE-2021-30596 in Chrome
Summary
by MITRE • 08/27/2021
Incorrect security UI in Navigation in Google Chrome on Android prior to 92.0.4515.131 allowed a remote attacker to spoof the contents of the Omnibox (URL bar) via a crafted HTML page.
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Analysis
by VulDB Data Team • 09/01/2021
The vulnerability identified as CVE-2021-30596 represents a critical security flaw in Google Chrome's navigation user interface on Android devices. This issue affects versions prior to 92.0.4515.131 and stems from an improper implementation of security indicators within the browser's omnibox component. The vulnerability specifically exploits the browser's handling of URL display and security warnings, creating a scenario where malicious actors can manipulate the visual presentation of web addresses to deceive users. The flaw resides in how Chrome renders security indicators and URL information within the navigation bar, potentially allowing attackers to present misleading information that appears legitimate to end users.
The technical nature of this vulnerability aligns with CWE-693, which addresses protection mechanism failures in web browsers. The flaw operates by leveraging the browser's rendering engine to manipulate how URL information is displayed to users, effectively bypassing the normal security mechanisms that should prevent such spoofing attacks. Attackers can craft malicious HTML pages that exploit the browser's trust model, causing the omnibox to display deceptive content that mimics legitimate websites. This manipulation occurs at the user interface level rather than at the network or protocol level, making it particularly insidious as it exploits user trust in familiar browser interfaces.
The operational impact of this vulnerability extends beyond simple phishing attacks, as it undermines fundamental security assumptions about URL verification and site authentication within Chrome. Users interacting with compromised pages may be misled into believing they are visiting legitimate websites when they are actually engaging with malicious content. This deception can lead to credential theft, financial fraud, or data exfiltration, as users may unknowingly provide sensitive information to attackers. The vulnerability is particularly dangerous in mobile environments where users may be less vigilant about URL verification due to smaller screen sizes and different interaction patterns compared to desktop browsers. The attack vector requires no local privileges or complex exploitation techniques, making it accessible to threat actors with minimal technical expertise.
Mitigation strategies for CVE-2021-30596 primarily involve updating to Chrome version 92.0.4515.131 or later, which includes patches addressing the security UI implementation. Organizations should implement comprehensive browser update policies to ensure all Android devices running Chrome are kept current with security patches. Additional protective measures include user education about recognizing suspicious URL patterns, implementing network-level security controls such as DNS filtering, and deploying browser security extensions that provide enhanced URL validation. Security teams should also monitor for indicators of compromise related to this vulnerability, particularly in environments where users may be exposed to untrusted web content. The vulnerability demonstrates the critical importance of maintaining up-to-date browser software and highlights the need for continuous security monitoring, as it operates within the ATT&CK framework under the technique of "Phishing" with specific relevance to "Spearphishing via UI Impersonation" and "Credential Access" tactics. Organizations should also consider implementing additional layers of security such as web application firewalls and content filtering solutions to protect against exploitation attempts targeting this class of vulnerability.