CVE-2023-21053
📋 TL;DR
This vulnerability allows remote attackers to read memory beyond intended boundaries in Android's cell broadcast message processing. It could disclose sensitive information without user interaction. Affects Android devices with vulnerable kernel versions.
💻 Affected Systems
- Android
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Remote attacker could read kernel memory, potentially exposing sensitive data like encryption keys, passwords, or other device information.
Likely Case
Information disclosure of limited memory contents, possibly revealing device state or configuration data.
If Mitigated
No impact if patched; unpatched devices remain vulnerable to information disclosure.
🎯 Exploit Status
Exploitation requires sending specially crafted cell broadcast messages; no authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: March 2023 Android security patch level
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2023-03-01
Restart Required: Yes
Instructions:
1. Check for system updates in Settings > System > System update. 2. Install March 2023 Android security patch. 3. Reboot device after installation.
🔧 Temporary Workarounds
Disable cell broadcast messages
androidPrevent processing of cell broadcast messages that could trigger the vulnerability
🧯 If You Can't Patch
- Segment vulnerable devices from untrusted networks
- Monitor for unusual cell broadcast traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check Android security patch level in Settings > About phone > Android version. If before March 2023, device is vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows March 2023 or later in Settings > About phone > Android version.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- SMS/cell broadcast processing errors in system logs
Network Indicators:
- Unusual cell broadcast traffic patterns
- SMS/CB messages from unexpected sources
SIEM Query:
source="android_system" AND ("sms_ExtractCbLanguage" OR "cell broadcast" OR "CVE-2023-21053")