CVE-2018-4174

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-04-03 · updated 2026-06-17

Description

An issue was discovered in certain Apple products. iOS before 11.3 is affected. macOS before 10.13.4 is affected. The issue involves the "Mail" component. It allows man-in-the-middle attackers to read S/MIME encrypted messages by leveraging an inconsistency in the user interface.

Affected products

Apple Iphone Os: before 11.3 — fixed in 11.3
macOS: before 10.13.4 — fixed in 10.13.4

How to fix

Upgrade to a fixed version: Apple Iphone Os 11.3; macOS 10.13.4. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/103581
http://www.securitytracker.com/id/1040604
http://www.securitytracker.com/id/1040608
https://support.apple.com/HT208692
https://support.apple.com/HT208693
http://www.securityfocus.com/bid/103581
http://www.securitytracker.com/id/1040604
http://www.securitytracker.com/id/1040608
https://support.apple.com/HT208692
https://support.apple.com/HT208693

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