CVE-2021-1023 in Android
Summary
by MITRE • 12/15/2021
In onCreate of RequestIgnoreBatteryOptimizations.java, there is a possible way to determine whether an app is installed, without query permissions, due to side channel information disclosure. This could lead to local information disclosure with no additional execution privileges needed. User interaction is needed for exploitation.Product: AndroidVersions: Android-12Android ID: A-195963373
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Analysis
by VulDB Data Team • 12/22/2021
This vulnerability resides in the Android operating system's handling of battery optimization requests and demonstrates a sophisticated side-channel information disclosure flaw. The issue manifests within the onCreate method of RequestIgnoreBatteryOptimizations.java, where an application can potentially determine the presence of other applications on the device without requiring explicit query permissions. This represents a significant privacy and security concern as it allows for unauthorized enumeration of installed applications through indirect means.
The technical flaw exploits the way Android processes battery optimization requests and creates a timing or behavioral side channel that reveals information about application installation status. Attackers can leverage this vulnerability to perform reconnaissance activities by observing differences in system behavior or response patterns when interacting with battery optimization APIs. The vulnerability does not require additional execution privileges or elevated permissions, making it particularly dangerous as it can be exploited from standard application contexts. The attack vector relies on user interaction, meaning that a malicious application would need to convince a user to perform a specific action such as opening a particular screen or interacting with a targeted interface element.
The operational impact of this vulnerability extends beyond simple application enumeration, potentially enabling more sophisticated attacks such as targeted malware delivery, social engineering campaigns, or comprehensive device profiling. An attacker could use this information to tailor subsequent attacks based on the installed applications, potentially identifying vulnerable configurations or applications with known security flaws. This information disclosure could also be combined with other vulnerabilities to create more comprehensive attack scenarios, making it a valuable primitive for advanced persistent threats.
From a cybersecurity perspective, this vulnerability aligns with CWE-200 (Information Exposure) and represents a form of side-channel attack that bypasses traditional permission-based security models. The issue demonstrates how seemingly innocuous system APIs can be abused to create information leakage channels that violate user privacy expectations. Security professionals should consider this vulnerability in the context of ATT&CK technique T1518 (Software Discovery) and T1082 (System Information Discovery) as it enables adversaries to gather device-specific information without traditional reconnaissance methods. The vulnerability underscores the importance of comprehensive security reviews of system APIs and the potential for unintended information disclosure through seemingly benign functionality.
Mitigation strategies should focus on implementing proper sandboxing of battery optimization APIs, ensuring that behavioral differences between application states do not reveal installation information, and considering the introduction of additional timing or randomization mechanisms to prevent side-channel exploitation. Android developers and security teams should also implement monitoring for unusual patterns in battery optimization API usage that might indicate exploitation attempts. Regular security updates and patches are essential to address this vulnerability, while users should be educated about the risks of interacting with untrusted applications that might attempt to exploit such information disclosure mechanisms.