CVE-2015-1527 in Android
Summary
by MITRE
Integer overflow in IAudioPolicyService.cpp in Android allows local users to gain privileges via a crafted application, aka Android Bug ID 19261727.
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Analysis
by VulDB Data Team • 11/16/2019
The vulnerability identified as CVE-2015-1527 represents a critical integer overflow flaw within the Android operating system's audio policy service implementation. This vulnerability exists in the IAudioPolicyService.cpp source file and specifically affects Android versions prior to 5.0. The flaw manifests when the system processes audio policy configuration requests, creating a condition where integer arithmetic operations can exceed their maximum representable values. This type of vulnerability falls under the CWE-190 category of Integer Overflow or Wraparound, which is a well-documented weakness in software security that occurs when an integer value exceeds its maximum capacity and wraps around to a smaller value. The vulnerability is particularly concerning because it allows local privilege escalation, meaning that an attacker with a malicious application running on the device can exploit this flaw to gain elevated system privileges.
The technical exploitation of this vulnerability occurs when a crafted application attempts to manipulate audio policy parameters through the Android audio framework. The integer overflow specifically affects the calculation of audio policy configuration values, particularly when dealing with large numerical inputs that exceed the bounds of the integer data type being used. When such overflow occurs, it can lead to memory corruption or unexpected behavior in the audio policy service, potentially allowing attackers to manipulate memory locations or bypass access controls. The Android operating system's audio policy service is responsible for managing audio routing, volume control, and device configuration policies, making it a critical system component that requires proper privilege controls. The vulnerability essentially creates a pathway for a local attacker to manipulate the audio policy service in a way that could compromise system integrity and allow for unauthorized access to privileged operations.
The operational impact of CVE-2015-1527 extends beyond simple privilege escalation, as it represents a fundamental weakness in the Android security model that could enable more sophisticated attacks. When successfully exploited, this vulnerability allows an attacker to execute code with system-level privileges, potentially enabling them to access sensitive data, modify system configurations, or even install malicious applications with elevated permissions. The attack vector requires only a local application to be present on the device, making it particularly dangerous as it can be exploited through seemingly benign applications that may be downloaded from untrusted sources. This vulnerability aligns with ATT&CK technique T1068 which covers 'Local Privilege Escalation', and specifically demonstrates how flaws in system services can be leveraged to achieve unauthorized system access. The impact is particularly severe because audio policy services are often running with elevated privileges and are integral to the device's core functionality.
Mitigation strategies for CVE-2015-1527 primarily focus on system updates and patch management, as the vulnerability was addressed in Android version 5.0 and subsequent releases. Organizations and individuals should prioritize updating their Android devices to versions that contain the security patches for this vulnerability, which typically include proper input validation and integer overflow protections in the audio policy service implementation. Additionally, system administrators should implement application whitelisting policies to prevent unauthorized applications from being installed on devices, particularly those that may attempt to exploit such vulnerabilities. Network monitoring solutions should be configured to detect anomalous audio policy service behavior or unusual privilege escalation attempts. The vulnerability serves as a reminder of the importance of secure coding practices in system services, particularly those that handle user input and perform arithmetic operations. Security teams should conduct regular vulnerability assessments of Android applications and system components to identify potential integer overflow conditions and other memory-related vulnerabilities that could be exploited for privilege escalation attacks.