CVE-2017-13231 in Android
Summary
by MITRE
In libmediadrm, there is an out-of-bounds write due to improper input validation. This could lead to local elevation of privileges with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android. Versions: 8.0, 8.1. Android ID: A-67962232.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 02/03/2021
The vulnerability identified as CVE-2017-13231 resides within the libmediadrm library component of Android operating systems, specifically affecting versions 8.0 and 8.1. This represents a critical security flaw that demonstrates the importance of proper input validation in system-level components. The issue manifests as an out-of-bounds write condition that occurs when the library fails to adequately validate input data during media DRM processing operations. Such vulnerabilities are particularly dangerous because they can be exploited to gain elevated system privileges without requiring any additional execution permissions or user interaction, making them highly attractive targets for attackers seeking to compromise Android devices.
The technical nature of this vulnerability falls under CWE-787, which specifically addresses out-of-bounds write conditions in software systems. This flaw occurs within the media DRM framework where the system processes digital rights management content for media playback. When malformed or unvalidated input data is processed by libmediadrm, the library fails to properly bounds-check array accesses, leading to memory corruption that can be leveraged for privilege escalation. The absence of user interaction requirements makes this vulnerability particularly concerning as it can be exploited automatically without any user involvement, potentially allowing attackers to gain root access to affected devices. The Android ID A-67962232 indicates this was properly tracked and addressed within the Android security framework.
The operational impact of CVE-2017-13231 extends beyond simple privilege escalation to potentially enable full system compromise. An attacker who successfully exploits this vulnerability could gain root-level access to the device, allowing them to modify system files, install malicious applications, access all user data, and potentially escalate their privileges to gain control over the entire Android operating system. This type of local privilege escalation vulnerability is particularly dangerous because it can be exploited by malicious applications already present on the device or through supply chain attacks that leverage the compromised media processing capabilities. The vulnerability's presence in the libmediadrm component means that any application that processes media content through the Android DRM system could potentially serve as an attack vector.
Mitigation strategies for CVE-2017-13231 should prioritize immediate system updates and patches from Android security teams. Organizations and users must ensure their Android devices are updated to versions that contain the patched libmediadrm library, which addresses the improper input validation that leads to the out-of-bounds write condition. Security teams should implement monitoring for suspicious privilege escalation attempts and ensure that media processing applications are properly sandboxed and validated. The vulnerability's classification under ATT&CK technique T1068, which covers local privilege escalation, indicates that defensive measures should include runtime application control, memory protection mechanisms, and regular security assessments of media processing components. Additionally, implementing network-level controls to prevent unauthorized application installation and maintaining comprehensive system monitoring can help detect exploitation attempts before they result in full system compromise.