What’s Vulnerable › Vulnerabilities

CVE-2018-4203

• Severity: high (CVSS 7.5 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: 2019-04-03 · updated 2026-06-17
• Weakness: CWE-125

Description

An out-of-bounds read was addressed with improved bounds checking. This issue affected versions prior to iOS 12, macOS Mojave 10.14, tvOS 12, watchOS 5.

Affected products

• Apple Iphone Os: before 12.0 — fixed in 12.0
• macOS: before 10.14 — fixed in 10.14
• Apple tvOS: before 12 — fixed in 12
• Apple watchOS: before 5.0 — fixed in 5.0

How to fix

Upgrade to a fixed version: Apple Iphone Os 12.0; macOS 10.14; Apple tvOS 12; Apple watchOS 5.0. Check the vendor advisory for mitigations.

References

• https://support.apple.com/kb/HT209106
• https://support.apple.com/kb/HT209107
• https://support.apple.com/kb/HT209108
• https://support.apple.com/kb/HT209139
• https://support.apple.com/kb/HT209193
• https://support.apple.com/kb/HT209106
• https://support.apple.com/kb/HT209107
• https://support.apple.com/kb/HT209108
• https://support.apple.com/kb/HT209139
• https://support.apple.com/kb/HT209193

Get alerted when CVE-2018-4203 or the next vulnerability affects your stack