CVE-2021-0607
📋 TL;DR
This vulnerability allows local attackers to write arbitrary data to hardware ports due to missing bounds checks in the iaxxx-codec driver. It enables local privilege escalation without requiring user interaction or additional execution privileges. Affects Android devices with vulnerable kernel versions.
💻 Affected Systems
- Android devices with Qualcomm audio codec hardware
📦 What is this software?
Android by Google
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to gain root privileges, install persistent malware, or brick the device through hardware manipulation.
Likely Case
Local privilege escalation allowing attackers to bypass application sandboxing and access sensitive data or system resources.
If Mitigated
Limited impact if SELinux policies restrict hardware access or if device has additional hardware protections.
🎯 Exploit Status
Requires local access and kernel driver knowledge. No public exploits known but vulnerability is straightforward for skilled attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: June 2021 Android Security Patch or later
Vendor Advisory: https://source.android.com/security/bulletin/pixel/2021-06-01
Restart Required: Yes
Instructions:
1. Apply June 2021 Android Security Patch via Settings > System > System update. 2. For custom kernels, apply commit fixing bounds check in iaxxx_calc_i2s_div function. 3. Reboot device after patch installation.
🔧 Temporary Workarounds
Disable vulnerable driver module
linuxPrevent loading of iaxxx-codec driver if not required
echo 'blacklist iaxxx-codec' >> /etc/modprobe.d/blacklist.conf
rmmod iaxxx-codec
🧯 If You Can't Patch
- Restrict physical access to devices and implement strict app installation policies
- Use SELinux policies to restrict hardware port access and monitor for privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and security patch level: Settings > About phone > Android version > Security patch level. If before June 2021, likely vulnerable.Check Version:
adb shell getprop ro.build.version.security_patchVerify Fix Applied:
Verify security patch level shows June 2021 or later. Check if /sys/module/iaxxx_codec exists and version matches patched driver.📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing iaxxx-codec driver errors or unexpected hardware writes
- SELinux denials for hardware port access
Network Indicators:
- None - local-only vulnerability
SIEM Query:
source="kernel" AND ("iaxxx" OR "hardware port write" OR "privilege escalation")