CVE-2021-25383
📋 TL;DR
This vulnerability allows attackers to execute arbitrary code on Samsung devices by exploiting improper input validation in the libsapextractor library's scmn_mfal_read() function. Attackers can achieve remote code execution on the mediaextractor process, potentially compromising device security. Affected devices are Samsung smartphones and tablets running vulnerable versions of the software.
💻 Affected Systems
- Samsung Galaxy smartphones
- Samsung Galaxy tablets
📦 What is this software?
Android by Google
Android by Google
Android by Google
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise allowing installation of persistent malware, data theft, and complete control over device functions including camera, microphone, and location tracking.
Likely Case
Remote code execution leading to data exfiltration, surveillance capabilities, and potential ransomware deployment on affected Samsung devices.
If Mitigated
Limited impact if patched, with potential denial of service or application crashes if exploitation attempts are blocked.
🎯 Exploit Status
Exploitation requires user interaction to open malicious media files, but no authentication needed. CVSS 9.0 indicates high severity and likely exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: SMR MAY-2021 Release 1 and later
Vendor Advisory: https://security.samsungmobile.com/securityUpdate.smsb?year=2021&month=5
Restart Required: Yes
Instructions:
1. Check for system updates in device Settings > Software update. 2. Download and install SMR MAY-2021 Release 1 or later. 3. Restart device after installation completes.
🔧 Temporary Workarounds
Disable automatic media processing
androidPrevent automatic parsing of media files by untrusted applications
Use trusted media sources only
allAvoid opening media files from unknown or untrusted sources
🧯 If You Can't Patch
- Isolate vulnerable devices from internet access and untrusted networks
- Implement application whitelisting to prevent execution of untrusted media processing apps
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Software information. If patch level is earlier than May 2021, device is vulnerable.Check Version:
Settings > About phone > Software information > Android security patch levelVerify Fix Applied:
Verify security patch level shows 'May 1, 2021' or later in device settings.📡 Detection & Monitoring
Log Indicators:
- MediaExtractor process crashes
- Unusual memory access patterns in media processing
- Suspicious file parsing activities
Network Indicators:
- Unexpected outbound connections after media file processing
- Data exfiltration patterns following media file access
SIEM Query:
process:MediaExtractor AND (event:crash OR memory_access:anomalous)