CVE Watch—

CVE-2021-30663

Apple Multiple Products WebKit Integer Overflow Vulnerability

CVSS

—

No CVSS

EPSS

3.7%

p88

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

3.5%EPSS · 30 days3.7%

2026-06-302026-07-17

KEV catalog record

Product

Apple / Multiple Products

Vulnerability

Apple Multiple Products WebKit Integer Overflow Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

Nov 17, 2021

Known ransomware use

Summary description

Apple iOS, iPadOS, macOS, tvOS, and Safari WebKit contain an integer overflow vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.

Required action

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2021-30663

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