CVE-2015-3878 in Android
Summary
by MITRE
Media Projection in Android 5.x before 5.1.1 LMY48T and 6.0 before 2015-10-01 allows attackers to bypass an intended screen-recording warning feature and obtain sensitive screen-snapshot information via a crafted application that references a long application name, aka internal bug 23345192.
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Analysis
by VulDB Data Team • 02/03/2018
The vulnerability CVE-2015-3878 represents a significant security flaw in Android's media projection functionality affecting versions 5.x before 5.1.1 and 6.0 before the 2015-10-01 security patch. This issue resides in the screen recording warning mechanism that was designed to alert users when applications attempt to capture their screen content. The flaw specifically targets the application name handling within the media projection API, creating a bypass condition that allows malicious applications to circumvent the intended security controls. The vulnerability manifests when an attacker crafts a malicious application with an excessively long application name that triggers a buffer handling issue in the system's screen recording notification mechanism.
The technical exploitation of this vulnerability occurs through the manipulation of application name length within the Android media projection framework. When an application attempts to initiate screen recording, the system displays a warning dialog to inform users about the potential screen capture. However, the flaw arises from improper bounds checking in the application name processing logic, where extremely long application names cause buffer overflows or memory corruption that bypasses the warning system. This allows the malicious application to silently capture screen content without user awareness, effectively undermining the security model designed to protect user privacy and sensitive information exposure.
From an operational impact perspective, this vulnerability creates a serious risk for user privacy and data protection across affected Android versions. Attackers can leverage this flaw to perform unauthorized screen captures without user consent, potentially accessing sensitive information such as passwords, personal data, financial information, or confidential business communications. The vulnerability is particularly concerning because it operates silently in the background, making detection difficult for end users who remain unaware that their screen content is being captured. Security researchers have classified this issue under CWE-121, which addresses stack-based buffer overflow conditions, and it aligns with ATT&CK technique T1113 for screen capture activities that bypass user awareness mechanisms.
Mitigation strategies for CVE-2015-3878 focus primarily on applying the relevant security patches released by Google as part of their regular security updates. Organizations and individuals should ensure their Android devices are updated to Android 5.1.1 LMY48T or later versions, or Android 6.0 with the 2015-10-01 security patch. System administrators should implement comprehensive mobile device management policies that enforce automatic security updates and monitor for vulnerable devices within their networks. Additionally, users should exercise caution when installing applications from untrusted sources and should regularly review their device permissions to ensure no suspicious applications have been granted screen recording capabilities. Network monitoring solutions can also help detect unusual screen capture activities that might indicate exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation and bounds checking in security-sensitive code areas, particularly in user-facing notification systems that are designed to protect against malicious activities.