CVE-2017-0870 in Android
Summary
by MITRE
An elevation of privilege vulnerability in the Android framework (libminikin). Product: Android. Versions: 5.1.1, 6.0, 6.0.1, 7.0, 7.1.1, 7.1.2, 8.0. Android ID A-62134807.
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Analysis
by VulDB Data Team • 12/12/2019
The vulnerability identified as CVE-2017-0870 represents a critical elevation of privilege flaw within the Android framework, specifically affecting the libminikin library component responsible for text layout and rendering operations. This vulnerability manifests in Android versions 5.1.1, 6.0, 6.0.1, 7.0, 7.1.1, 7.1.2, and 8.0, making it a widespread issue across multiple Android release lines. The Android ID A-62134807 indicates this was properly tracked and documented within Google's internal vulnerability management system, highlighting its significance in the mobile security landscape.
The technical root cause of this vulnerability lies within improper input validation and memory handling within the libminikin library, which processes text rendering operations for Android applications. Attackers can exploit this flaw by crafting malicious text input that triggers a buffer overflow or memory corruption condition during text layout processing. This occurs when the system fails to properly validate font data or text formatting parameters before processing them through the vulnerable text rendering engine. The flaw essentially allows an unprivileged application to manipulate memory structures that should be protected, potentially enabling arbitrary code execution with elevated privileges. This type of vulnerability maps to CWE-121, which describes stack-based buffer overflow conditions, and CWE-122, which covers heap-based buffer overflow scenarios.
The operational impact of CVE-2017-0870 is severe as it enables attackers to escalate their privileges from regular application level access to system-level control without requiring user interaction or physical access to the device. An attacker who can successfully exploit this vulnerability can gain complete control over the affected Android device, potentially accessing sensitive user data, installing malicious applications, modifying system files, or even creating persistent backdoors. The vulnerability's exploitation does not require user interaction, making it particularly dangerous as it can be triggered automatically when the device processes malicious text content through standard applications or system services. This aligns with ATT&CK technique T1068, which describes the use of local privilege escalation techniques to gain system-level access.
Mitigation strategies for this vulnerability primarily involve applying the official Android security patches released by Google, which address the underlying memory handling issues in the libminikin library. Organizations and users should prioritize immediate deployment of the security updates, as the vulnerability remains exploitable in unpatched systems. Additionally, implementing application whitelisting policies, monitoring for unusual text processing activities, and maintaining regular security audits can help detect potential exploitation attempts. Network-level defenses should focus on identifying suspicious text-based communications that might contain crafted payloads designed to trigger this vulnerability. The vulnerability's classification as a privilege escalation issue also necessitates careful review of application permissions and access controls within the Android environment.