CVE-2021-39783 Missing authorization in Android

What is CVE-2021-39783?

CVE-2021-39783 is a high-severity missing authorization vulnerability in Google Android, published on 30 Mar 2022. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In rcsservice, there is a possible way to modify TTY mode due to a missing permission check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-12LAndroid ID: A-197960597

Weakness: CWE-269

Which versions are affected by CVE-2021-39783?

It affects 1 product.

Products include Google Android.

How do I fix CVE-2021-39783?

No fix has been published for CVE-2021-39783 yet. Limit exposure of the affected software until one is available.

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

Is CVE-2021-39783 being exploited?

There is no known exploitation of CVE-2021-39783 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 GHSA-38hv-gjp4-4fjh.