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IMMUNITYSEC

CVE-2021-30663

7.8
HIGH
CVSS 3.1
EPSS 3.5% · 89th pctCISA KEV · Exploited in the wild
2021-09-08•Updated 2025-10-21•KEV 2021-11-03
CISA Known Exploited Vulnerabilities

Apple Multiple Products WebKit Integer Overflow Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV
2021-11-03
Remediation due
2021-11-17

Required action
Apply updates per vendor instructions.

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

Description

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.

Severity

CVSS 3.1 · CISA7.8 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC · CISA-ADP
Exploitationactive
Automatableno
Technical impacttotal

Affected Products

VendorProductAffected versions
ApplemacOS
unspecified to <11.3
ApplemacOS
unspecified to <14.5
ApplemacOS
unspecified to <12.5
ApplemacOS
unspecified to <14.6
ApplemacOS
unspecified to <14.1

References

5 Links

Record Details

Published
2021-09-08
Last updated
2025-10-21
Assigner (CNA)
apple
Credited to
-

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.