CVE-2024-23706: Google Android Privilege Escalation Flaw

CVE-2024-23706 Overview

CVE-2024-23706 is an improper input validation vulnerability affecting Android's HealthFitness module. The flaw exists in multiple locations within the Android platform and enables a possible bypass of health data permissions due to insufficient validation of input data. This vulnerability could allow an attacker with local access to escalate privileges without requiring any user interaction or additional execution privileges.

Critical Impact

Local privilege escalation enabling unauthorized access to sensitive health data on Android 14 devices without user interaction.

Affected Products

• Google Android 14.0
• Android HealthFitness module (packages/modules/HealthFitness)

Discovery Timeline

• May 7, 2024 - CVE-2024-23706 published to NVD
• December 17, 2024 - Last updated in NVD database

Technical Details for CVE-2024-23706

Vulnerability Analysis

This vulnerability stems from improper input validation (CWE-20) within Android's HealthFitness module. The flaw allows attackers to bypass the permission framework protecting sensitive health data stored on Android devices. Since the vulnerability can be exploited locally without requiring elevated privileges or user interaction, it presents a significant risk for devices where an attacker has already gained a foothold through another vector, such as a malicious application.

The attack requires local access to the device but does not need special execution privileges, making it exploitable by any application running on the device. The impact affects confidentiality, integrity, and availability of the targeted data, as successful exploitation grants the attacker elevated privileges within the health data context.

Root Cause

The root cause of CVE-2024-23706 lies in improper input validation across multiple locations within the Android HealthFitness module. The validation logic fails to properly sanitize or verify input data before processing, allowing malicious inputs to bypass the permission checks that normally protect access to health data. This insufficient validation enables privilege escalation by circumventing the intended access control mechanisms.

Attack Vector

The attack vector is local, meaning an attacker must have some level of access to the target Android device. This could be achieved through a malicious application installed on the device or through physical access. Once positioned locally, the attacker can craft malicious input that bypasses the health data permission checks without requiring any user interaction.

The exploitation flow involves:

1. Gaining local access to an Android 14 device (e.g., via malicious app installation)
2. Crafting input that exploits the validation weakness in the HealthFitness module
3. Bypassing health data permission checks to escalate privileges
4. Gaining unauthorized access to protected health information

Technical details regarding the specific exploitation mechanism can be found in the Google Android Commit Update that addresses this vulnerability.

Detection Methods for CVE-2024-23706

Indicators of Compromise

• Unusual application behavior attempting to access health data without proper permissions
• Unexpected privilege changes or permission grants related to health data APIs
• Anomalous inter-process communication (IPC) patterns targeting the HealthFitness module
• Applications making repeated or malformed requests to health data endpoints

Detection Strategies

• Monitor for applications attempting to access health data APIs without appropriate permission grants
• Implement runtime application self-protection (RASP) solutions to detect permission bypass attempts
• Audit system logs for anomalous access patterns to the HealthFitness module
• Deploy mobile threat defense (MTD) solutions capable of detecting privilege escalation attempts

Monitoring Recommendations

• Enable verbose logging for the Android HealthFitness module during incident investigation
• Monitor device management solutions for indicators of compromised applications
• Implement behavioral analysis to detect applications exhibiting unusual permission access patterns
• Review installed applications regularly for known malicious packages

How to Mitigate CVE-2024-23706

Immediate Actions Required

• Apply the May 2024 Android Security Bulletin patches immediately
• Ensure all Android 14 devices are updated to the latest security patch level
• Review installed applications and remove any untrusted or suspicious apps
• Enable Google Play Protect to help detect potentially harmful applications

Patch Information

Google has released a security patch addressing this vulnerability as part of the Android Security Bulletin May 2024. The fix is available in commit 6e6896c3fd8139779ff8d51a99ee06667e849d87 for the HealthFitness module, which can be reviewed at the Google Android Commit Update.

Organizations managing Android device fleets should prioritize deployment of the May 2024 security patch level or later to all Android 14 devices.

Workarounds

• Restrict installation of applications to trusted sources only (Google Play Store with Play Protect enabled)
• Implement mobile device management (MDM) policies to control application installation and permissions
• Consider revoking health data permissions from non-essential applications until patching is complete
• Use application sandboxing and isolation technologies where available

# Verify Android security patch level via ADB
adb shell getprop ro.build.version.security_patch
# Expected output should be 2024-05-01 or later for patched devices