CVE-2021-25366 in Internet
Summary
by MITRE • 03/25/2021
Improper access control in Samsung Internet prior to version 13.2.1.70 allows physically proximate attackers to bypass the secret mode's authentication.
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Analysis
by VulDB Data Team • 04/05/2021
The vulnerability identified as CVE-2021-25366 represents a critical access control flaw in Samsung Internet browser versions prior to 13.2.1.70. This issue specifically affects the secret mode authentication mechanism, which is designed to provide users with a private browsing environment where sensitive activities remain hidden from unauthorized access. The flaw allows attackers who are physically proximate to a device to bypass the authentication requirements that should protect this confidential browsing mode.
The technical implementation of this vulnerability stems from insufficient validation of authentication credentials within the secret mode functionality. When users activate secret mode in Samsung Internet, the application should require proper authentication before granting access to the private browsing environment. However, the flawed implementation fails to properly verify user credentials or maintain secure session states, creating an exploitable condition where unauthorized individuals can gain access without proper authentication. This represents a fundamental breakdown in the application's security architecture and violates core principles of access control as defined by CWE-284 which addresses improper access control mechanisms.
The operational impact of this vulnerability extends beyond simple privacy concerns to potentially enable various malicious activities. An attacker with physical proximity to a device can access private browsing sessions, potentially exposing sensitive personal information, login credentials, financial data, or confidential communications that users expected to remain protected. This threat vector is particularly concerning because it requires minimal technical expertise to exploit and can be executed in environments where physical access is possible, such as public spaces, shared work environments, or during device theft scenarios. The vulnerability directly aligns with ATT&CK technique T1566 which covers credential harvesting and access to sensitive data through physical access methods.
The security implications of this flaw demonstrate a failure in implementing proper security controls for mobile applications, particularly those handling sensitive user data. The vulnerability essentially creates a backdoor into private browsing sessions that should be protected from unauthorized access, undermining the trust users place in the application's privacy features. Organizations and users relying on Samsung Internet's secret mode for confidential activities face significant risks as this flaw can be exploited without requiring network connectivity or sophisticated attack infrastructure, making it particularly dangerous in mobile environments where physical security is often compromised.
Mitigation strategies should focus on immediate remediation through updating to Samsung Internet version 13.2.1.70 or later, which contains the necessary patches to address the authentication bypass vulnerability. Additionally, users should be educated about the risks of physical access to their devices and consider additional security measures such as device encryption, secure lock screens, and biometric authentication. Security teams should also implement monitoring for suspicious access patterns and consider device management policies that enforce security updates. The vulnerability highlights the importance of proper access control implementation in mobile applications and serves as a reminder that even seemingly simple security features like private browsing modes require rigorous security testing to prevent authentication bypass attacks that can compromise user privacy and data protection.