What is CVE-2018-21052?

CVE-2018-21052 is a critical-severity vulnerability in Google Android, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2020-04-08.

How severe is CVE-2018-21052?

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

Buffer overflow in Google Android

CVE-2018-21052

An issue was discovered on Samsung mobile devices with N(7.x) and O(8.X) (Exynos chipsets) software. There is incorrect usage of shared memory in the vaultkeeper Trustlet, leading to arbitrary code execution. The Samsung ID is SVE-2018-12855 (October 2018).

Vulnerability class: Buffer Overflow

Published 2020-04-08 · 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: 0.008 (55.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 55.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Google Android — versions 7.0, 7.1.0, 7.1.1

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

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

Frequently asked questions

What is CVE-2018-21052?: CVE-2018-21052 is a critical-severity vulnerability in Google Android, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2020-04-08.
How severe is CVE-2018-21052?: Critical severity. CVSS v3 base score is 9.8 out of 10.