What is CVE-2018-4409?

CVE-2018-4409 is a medium-severity vulnerability in Apple Icloud, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2019-04-03.

How severe is CVE-2018-4409?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Resource exhaustion in Apple Icloud

CVE-2018-4409

A resource exhaustion issue was addressed with improved input validation. This issue affected versions prior to iOS 12.1, tvOS 12.1, Safari 12.0.1, iTunes 12.9.1, iCloud for Windows 7.8.

Vulnerability class: DoS (Denial of Service)

Published 2019-04-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.016 (75.4th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 75.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000

Affected products

Apple Icloud
Apple Iphone OS
Apple Itunes
Apple Safari
Apple tvOS
Microsoft Windows
iOS, tvOS, Safari, Itunes For Windows, Icloud Windows — versions Versions prior to: iOS 12.1, tvOS 12.1, Safari 12.0.1, iTunes 12.9.1, iCloud for Windows 7.8

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

support.apple.com/kb/HT209192 (Vendor Advisory)
support.apple.com/kb/HT209194 (Vendor Advisory)
support.apple.com/kb/HT209197 (Vendor Advisory)
support.apple.com/kb/HT209198 (Vendor Advisory)
support.apple.com/kb/HT209196 (Vendor Advisory)

Frequently asked questions

What is CVE-2018-4409?: CVE-2018-4409 is a medium-severity vulnerability in Apple Icloud, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2019-04-03.
How severe is CVE-2018-4409?: Medium severity. CVSS v3 base score is 6.5 out of 10.