CVE-2016-2422 in Android
Summary
by MITRE
Wi-Fi in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, and 6.x before 2016-04-01 does not prevent use of a Wi-Fi CA certificate in an unrelated CA role, which allows attackers to gain privileges via a crafted application, as demonstrated by obtaining Signature or SignatureOrSystem access, aka internal bug 26324357.
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Analysis
by VulDB Data Team • 07/12/2022
The vulnerability described in CVE-2016-2422 represents a critical certificate validation flaw within the Android Wi-Fi security framework that affects multiple versions of the operating system. This issue stems from insufficient certificate role validation mechanisms that fail to properly enforce the intended use of certificate authority certificates within the Wi-Fi authentication process. The flaw allows malicious applications to exploit a certificate misconfiguration where a Wi-Fi certificate authority certificate can be improperly utilized in contexts where it was not originally intended to function, creating a significant privilege escalation vector.
The technical implementation of this vulnerability occurs at the certificate validation layer within Android's Wi-Fi subsystem where the system does not adequately verify that a certificate being used for Wi-Fi authentication is appropriate for the specific role it is being employed in. This misconfiguration enables attackers to craft malicious applications that can manipulate certificate trust relationships, effectively bypassing the intended security boundaries that should prevent a certificate from being used across unrelated security contexts. The vulnerability specifically targets the certificate authority validation process where certificates are accepted without proper role checking, allowing a certificate designated for one purpose to be used for another, potentially unauthorized function.
From an operational perspective, this vulnerability creates a severe security risk that can be exploited to gain elevated privileges within the Android system. Attackers can leverage this flaw to obtain Signature or SignatureOrSystem access levels, which provide extensive system-level capabilities including access to sensitive system components, the ability to install malicious applications with system-level privileges, and potential access to protected data and services. The impact extends beyond simple privilege escalation as it can enable attackers to establish persistent access points within the device and potentially compromise the entire security architecture of the affected Android versions.
The vulnerability aligns with CWE-295 which addresses improper certificate validation and improper certificate trust validation issues. This weakness specifically manifests as an improper validation of certificate usage roles within the Android security framework, creating a trust boundary violation that can be exploited through malicious application deployment. The attack vector follows the ATT&CK framework's privilege escalation techniques where adversaries leverage system-level vulnerabilities to gain elevated access rights. The flaw demonstrates poor implementation of certificate-based security controls and highlights the importance of proper certificate role enforcement in mobile security architectures.
Mitigation strategies for this vulnerability require immediate system updates to the patched Android versions that address the certificate validation logic. Organizations should implement comprehensive patch management processes to ensure all affected devices receive the necessary security updates. Additionally, security administrators should consider implementing network monitoring solutions that can detect anomalous certificate usage patterns and potential exploitation attempts. Device administrators should also review and restrict Wi-Fi certificate installation permissions, ensuring that only trusted applications can install certificates into the system trust store. The vulnerability underscores the importance of maintaining up-to-date security patches and proper certificate management practices within mobile environments, as this flaw could be exploited in targeted attacks against specific devices or networks.