What is CVE-2021-30928?

CVE-2021-30928 is a high-severity vulnerability in Apple Icloud, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2021-08-24.

How severe is CVE-2021-30928?

High severity. CVSS v3 base score is 7.8 out of 10.

Buffer overflow in Apple Icloud

CVE-2021-30928

A memory corruption issue was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.6, watchOS 8, tvOS 15, iOS 14.8 and iPadOS 14.8, iOS 15 and iPadOS 15. Processing a maliciously crafted image may lead to arbitrary code execution.

Vulnerability class: Buffer Overflow

Published 2021-08-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.014 (72.0th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 72.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Apple Icloud — versions 13.0
Apple Ipados
Apple Iphone OS
Apple macOS — versions unspecified
Apple tvOS — versions unspecified
Apple watchOS — versions unspecified

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

Frequently asked questions

What is CVE-2021-30928?: CVE-2021-30928 is a high-severity vulnerability in Apple Icloud, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2021-08-24.
How severe is CVE-2021-30928?: High severity. CVSS v3 base score is 7.8 out of 10.