What is CVE-2018-21065?

CVE-2018-21065 is a critical-severity vulnerability in Google Android, classified under Integer Underflow. CVSS score: 9.8/10. Published 2020-04-08.

How severe is CVE-2018-21065?

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

Integer overflow in Google Android

CVE-2018-21065

An issue was discovered on Samsung mobile devices with M(6.0), N(7.x), and O(8.x) software. There is an integer underflow in eCryptFS because of a missing size check. The Samsung ID is SVE-2017-11855 (August 2018).

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: 0.004 (36.0th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Google Android — versions 6.0, 7.0, 7.1.0

Weakness classification (CWE)

CWE-191 — Integer Underflow

References

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

Frequently asked questions

What is CVE-2018-21065?: CVE-2018-21065 is a critical-severity vulnerability in Google Android, classified under Integer Underflow. CVSS score: 9.8/10. Published 2020-04-08.
How severe is CVE-2018-21065?: Critical severity. CVSS v3 base score is 9.8 out of 10.