SARA / Free Tools / CVE / CVE-2021-30663

CVE-2021-30663 — Apple Multiple Products WebKit Integer Overflow 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.

CVSS
— —
EPSS
1.20% (top 21.30%)
CWE
—
Published
2021-09-08T14:49:41.000Z
Last modified
2025-10-21T23:25:34.065Z
CVSS vector
—
CISA KEV — Actively Exploited
Added to KEV
2021-11-03
BOD 22-01 due
2021-11-17
Ransomware use
Unknown
View KEV detail
CVE-2021-30663 on CISA KEV →

01What is 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.

02Affected products

VendorProductVersions
ApplemacOSunspecified
ApplemacOSunspecified
ApplemacOSunspecified
ApplemacOSunspecified
ApplemacOSunspecified

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2021-11-03. Ransomware use: Unknown.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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