CVE-2021-39807 : Vulnerability Insights and Analysis
Learn about CVE-2021-39807, a vulnerability in Android allowing local privilege escalation from the Guest account without additional execution privileges.
Android NFC vulnerability allowing local privilege escalation.
Understanding CVE-2021-39807
A vulnerability in Android versions 10, 11, 12, and 12L that could enable NFC from the Guest account without proper permission checks.
What is CVE-2021-39807?
- Detected in handleNfcStateChanged of SecureNfcEnabler.java
- Enables NFC from the Guest account without permission check
- Allows local escalation of privilege without additional execution privileges
The Impact of CVE-2021-39807
- Potential local escalation of privilege from the Guest account
- No user interaction required
- Android versions 10, 11, 12, and 12L affected
- Android ID: A-209446496
Technical Details of CVE-2021-39807
A deep dive into the technical aspects of the CVE.
Vulnerability Description
- Missing permission check in handleNfcStateChanged
- Allows enabling NFC from Guest account
Affected Systems and Versions
- Product: Android
- Versions: Android-10, Android-11, Android-12, Android-12L
Exploitation Mechanism
- No additional execution privileges needed
- Enables NFC from the Guest account
Mitigation and Prevention
Steps to mitigate and prevent exploitation of CVE-2021-39807
Immediate Steps to Take
- Apply security patches from Android
- Limit access to vulnerable systems
Long-Term Security Practices
- Regular security audits and checks
- Enforce the principle of least privilege
Patching and Updates
- Stay updated with security bulletins
- Apply patches promptly