Is CVE-2021-39640 actively exploited?

No active exploitation of CVE-2021-39640 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-39640 be exploited remotely?

No. CVE-2021-39640 requires local access to exploit.

What is the CVSS score of CVE-2021-39640?

CVE-2021-39640 has a CVSS score of 7.8 (HIGH).

HOME VULNERABILITIESCVE-2021-39640

HIGH

CVE-2021-39640

CWE-667Published: December 15, 2021· Updated: Jun 17, 2026

7.8

CVSS v3.1

Official Description

In __dwc3_gadget_ep0_queue of ep0.c, there is a possible out of bounds write due to improper locking. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-157294279References: N/A

NVD Source

Technical Analysis

CVE-2021-39640 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.8.