Actively exploited in the wild
Apple Multiple Products WebKit Integer Overflow Vulnerability
Apple - Multiple Products · Listed in the CISA KEV since 2021-11-03. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-30663
HighCVSS 8.8KEVSummary
An integer overflow was addressed with improved input validation. This issue is fixed in iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution.
Risk Assessment
Enables remote code execution after visiting a malicious website. Risk affects all users of unpatched Apple devices.
Recommendation
Update Apple systems to the specified versions (iOS 14.5.1, iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1).
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Original NVD description (English source)
An integer overflow was addressed with improved input validation. This issue is fixed in iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, Safari 14.1.1, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution.