CVE-2021-30663 on CISA KEV

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.

01What CISA says about this vulnerability

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.

02Required action — verbatim from CISA

Apply updates per vendor instructions.

03Notes & references

• support.apple.com — https://support.apple.com/en-us/HT212532
• support.apple.com — https://support.apple.com/en-us/HT212534
• support.apple.com — https://support.apple.com/en-us/HT212341
• support.apple.com — https://support.apple.com/en-us/HT212335
• support.apple.com — https://support.apple.com/en-us/HT212336

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

Vendor	Product	Versions
Apple	macOS	unspecified
Apple	macOS	unspecified
Apple	macOS	unspecified
Apple	macOS	unspecified
Apple	macOS	unspecified

06Detection

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection:

Open in Sigma generator →