CVE-2021-39639 Missing authorization in Android

What is CVE-2021-39639?

CVE-2021-39639 is a medium-severity missing authorization vulnerability in Google Android, published on 15 Dec 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In TBD of fvp.c, there is a possible way to glitch CPU behavior due to a missing permission check. This could lead to local escalation of privilege with physical access to device internals with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-198291476References: N/A

Weakness: CWE-862

Which versions are affected by CVE-2021-39639?

It affects 1 product.

Products include Google Android.

How do I fix CVE-2021-39639?

Apply the vendor's patch.

Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.

Is CVE-2021-39639 being exploited?

There is no known exploitation of CVE-2021-39639 in the wild and no public exploit code.

Other vulnerabilities in Google Android

• CVE-2026-58704 Google Pixel Improper Authorization Exploited High 8.8
• CVE-2025-48543 Android Runtime Use-After-Free Exploited High 8.8
• CVE-2023-35674 Android Framework Privilege Escalation Exploited High 8.8
• CVE-2025-48595 Android Framework Integer Overflow Exploited High 8.4
• CVE-2024-32896 Android Pixel Privilege Escalation Exploited High 8.1

All Google Android vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as A-198291476, GHSA-xj6m-g8xh-h3xc, PUB-A-198291476.