CVE-2021-39686: Race Condition
In several functions of binder.c, there is a possible way to represent the wrong domain to SELinux due to a race condition. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 4.19.249-2Fixed in 4.19.289-2Fixed in 6.1.66-1Fixed in 6.1.69-1Fixed in 6.5.13-1Fixed in 6.6.9-1 - Upgrade
Upgrade
android/:linux_kernel:to a version that resolves this vulnerability.Fixed in :2022-03-05
Event History
Frequently Asked Questions
What is CVE-2021-39686?
CVE-2021-39686 is a vulnerability in Android's binder.c file that allows for the incorrect representation of the SELinux domain due to a race condition.
What is the severity of CVE-2021-39686?
CVE-2021-39686 has a severity level of 7, which is considered high.
How does CVE-2021-39686 lead to privilege escalation?
CVE-2021-39686 can lead to local escalation of privilege without requiring additional execution privileges.
Is user interaction required for CVE-2021-39686 exploitation?
No, user interaction is not needed for the exploitation of CVE-2021-39686.
How can I fix CVE-2021-39686?
To fix CVE-2021-39686, update your Android device to the recommended versions provided by Google or Debian.