CVE-2021-39809 : Exploit Details and Defense Strategies

This CVE-2021-39809 article provides details about a vulnerability affecting Android versions 10, 11, 12, and 12L, leading to remote information disclosure.

Understanding CVE-2021-39809

CVE-2021-39809 is an information disclosure vulnerability in the avrc_ctrl_pars_vendor_rsp function of avrc_pars_ct.cc in Android.

What is CVE-2021-39809?

This vulnerability results from a missing bounds check in the mentioned function, potentially causing an out-of-bounds read. It can allow for remote information disclosure without requiring additional execution privileges or user interaction.

The Impact of CVE-2021-39809

The vulnerability could lead to remote information disclosure, posing a risk to the confidentiality of data.

Technical Details of CVE-2021-39809

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The flaw in avrc_ctrl_pars_vendor_rsp of avrc_pars_ct.cc allows for an out-of-bounds read due to the absence of a bounds check.

Affected Systems and Versions

Affected Product: Android
Affected Versions: Android-10, Android-11, Android-12, Android-12L

Exploitation Mechanism

The vulnerability does not require user interaction for exploitation, making it potentially exploitable remotely.

Mitigation and Prevention

Understanding how to mitigate the vulnerability and prevent similar issues is crucial.

Immediate Steps to Take

Apply official patches and updates from the Android security bulletin.
Monitor Google's security advisories for any further recommendations.

Long-Term Security Practices

Regularly update the Android OS to the latest version.
Implement network security measures to reduce the risk of remote exploitation.
Conduct periodic security assessments and audits.

Patching and Updates

Stay informed about security updates and patch releases from the official Android security bulletin.