CVE-2021-1799: Apple Ipad OS

Medium severity, CVSS 6.5. EPSS: 1.8% chance of exploitation in the next 30 days.

A port redirection issue was addressed with additional port validation. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. A malicious website may be able to access restricted ports on arbitrary servers.

Affected products

• Apple Ipad OS: before 14.4 (fixed in 14.4)
• Apple iPhone OS: before 14.4 (fixed in 14.4)
• Apple macOS: from 11.0.1, before 11.2 (fixed in 11.2)
• Apple Safari: before 14.0.3 (fixed in 14.0.3)
• Apple tvOS: before 14.4 (fixed in 14.4)
• Apple watchOS: before 7.3 (fixed in 7.3)
• Fedoraproject Fedora: version 32 only; version 33 only
• WebKitGTK WebKitGTK: before 2.30.6 (fixed in 2.30.6)

Published 2021-04-02. Last modified 2026-06-17.