CVE-2024-20840 in Voice Recorder
Summary
by MITRE • 03/05/2024
Improper access control in Samsung Voice Recorder prior to versions 21.5.16.01 in Android 12 and Android 13, 21.4.51.02 in Android 14 allows physical attackers using hardware keyboard to use VoiceRecorder on the lock screen.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/15/2025
The vulnerability CVE-2024-20840 represents a critical access control flaw in Samsung's Voice Recorder application that affects multiple Android versions including Android 12, 13, and 14. This weakness stems from inadequate authorization mechanisms that permit unauthorized physical access to voice recording functionality while the device is locked. The vulnerability specifically manifests when attackers possess physical access to the device and can utilize a hardware keyboard to interact with the application interface. This issue falls under the CWE-284 access control weakness category, which encompasses improper access control implementations that allow unauthorized users to access protected resources or functions. The vulnerability enables attackers to bypass normal security boundaries that should prevent application usage during device lock states, creating a significant security risk for users who may have sensitive information recorded without their knowledge or consent.
The technical implementation of this vulnerability exploits the lack of proper authentication checks within the Voice Recorder application's lock screen interface. When a device is locked, normal security protocols should prevent access to most applications including those with recording capabilities. However, the flaw allows attackers with physical access to use keyboard inputs to navigate and activate the voice recorder functionality directly from the lock screen. This bypass occurs because the application fails to properly validate user authentication status before allowing access to recording features. The vulnerability specifically targets the lock screen interaction model where hardware keyboard inputs can be processed by the application without proper verification of the device's locked state. This type of attack vector aligns with ATT&CK technique T1547.001 for registry run keys and T1059.001 for command and scripting interpreter, as it enables unauthorized execution of recording functions through legitimate device interfaces.
The operational impact of this vulnerability extends beyond simple privacy concerns to encompass potential data breaches and unauthorized surveillance capabilities. Attackers can record sensitive conversations, meetings, or personal communications without the device owner's knowledge or consent, creating risks for corporate espionage, personal privacy violations, and potential legal complications. The vulnerability is particularly concerning because it requires minimal attack sophistication - only physical access to the device and availability of a hardware keyboard. This makes it a significant risk for devices that may be lost, stolen, or accessed by unauthorized individuals in public or private settings. The vulnerability affects users across multiple Android versions, indicating a systemic issue in Samsung's implementation of lock screen security controls for voice recording applications. Organizations using Samsung devices may face compliance issues with privacy regulations such as GDPR, HIPAA, or other data protection frameworks that require proper access controls and user consent for audio recording activities.
Samsung has addressed this vulnerability through software updates released as part of versions 21.5.16.01 for Android 12 and 13, and 21.4.51.02 for Android 14. These updates implement proper authentication checks that prevent unauthorized access to voice recording functionality during device lock states. System administrators and users should immediately apply these updates to mitigate the risk of unauthorized recording access. Additional mitigations include enabling strong device encryption, implementing robust screen lock mechanisms such as biometric authentication, and establishing policies for secure device handling. Organizations should also consider deploying mobile device management solutions that can enforce security policies and monitor for unauthorized application access. The vulnerability highlights the importance of proper access control implementation in mobile applications and serves as a reminder that applications with sensitive capabilities must properly validate user authentication status before granting access to protected functions. Security professionals should conduct regular vulnerability assessments of mobile applications to identify similar access control weaknesses that could compromise user privacy and data security.