What is CVE-2018-21040?

CVE-2018-21040 is a high-severity vulnerability in Google Android, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2020-04-08.

How severe is CVE-2018-21040?

High severity. CVSS v3 base score is 8.1 out of 10.

Use After Free in Google Android

CVE-2018-21040

An issue was discovered on Samsung mobile devices with O(8.x) and P(9.0) (Exynos 9810 chipsets) software. There is a race condition with a resultant use-after-free in the g2d driver. The Samsung ID is SVE-2018-12959 (December 2018).

Vulnerability class: Race Condition

Published 2020-04-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (21.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Google Android — versions 8.0, 8.1, 9.0
Samsung Exynos 9810

Weakness classification (CWE)

References

security.samsungmobile.com/securityUpdate.smsb (Vendor Advisory)

Frequently asked questions

What is CVE-2018-21040?: CVE-2018-21040 is a high-severity vulnerability in Google Android, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2020-04-08.
How severe is CVE-2018-21040?: High severity. CVSS v3 base score is 8.1 out of 10.