What’s Vulnerable › Vulnerabilities

CVE-2021-1799

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-04-02 · updated 2026-06-17

Description

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: 32, 33
• Webkit: before 2.30.6 — fixed in 2.30.6

How to fix

Upgrade to a fixed version: Apple Ipad Os 14.4; Apple Iphone Os 14.4; Apple macOS 11.2; Apple Safari 14.0.3; Apple tvOS 14.4; Apple watchOS 7.3; Webkit 2.30.6. Check the vendor advisory for mitigations.

References

• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN6ZOD62CTO54CHTMJTHVEF6R2Y532TJ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/
• https://security.gentoo.org/glsa/202104-03
• https://support.apple.com/en-us/HT212146
• https://support.apple.com/en-us/HT212147
• https://support.apple.com/en-us/HT212148
• https://support.apple.com/en-us/HT212149
• https://support.apple.com/en-us/HT212152
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN6ZOD62CTO54CHTMJTHVEF6R2Y532TJ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/
• https://security.gentoo.org/glsa/202104-03
• https://support.apple.com/en-us/HT212146

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