What is CVE-2023-21066?

CVE-2023-21066 is a critical-severity vulnerability in Google Android, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2023-06-28.

How severe is CVE-2023-21066?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Google Android

CVE-2023-21066

In cd_CodeMsg of cd_codec.c, there is a possible out of bounds write due to a heap buffer overflow. This could lead to remote code execution with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-250100597References: N/A

Vulnerability class: Buffer Overflow

Published 2023-06-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (41.6th percentile), scored 2026-10-08.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Google Android
Android — versions Android kernel

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

source.android.com/security/bulletin/pixel/2023-06-01 (Vendor Advisory)

Frequently asked questions

What is CVE-2023-21066?: CVE-2023-21066 is a critical-severity vulnerability in Google Android, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2023-06-28.
How severe is CVE-2023-21066?: Critical severity. CVSS v3 base score is 9.8 out of 10.