How severe is CVE-2021-30952?

CVE-2021-30952 has a CVSS 3.1 base score of 8.8 (HIGH). EPSS estimates a 7.0% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-30952: Apple Multiple Products Integer Overflow or

CISA Known Exploited Vulnerabilities

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

Added to KEV

2026-03-05

Remediation due

2026-03-26

Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA notes
https://support.apple.com/en-us/HT212975 ; https://support.apple.com/en-us/HT212976 ; https://support.apple.com/en-us/HT212978 ; https://support.apple.com/en-us/HT212980 ; https://support.apple.com/en-us/HT212982 ; https://nvd.nist.gov/vuln/detail/CVE-2021-30952

Description

An integer overflow was addressed with improved input validation. This issue is fixed in tvOS 15.2, macOS Monterey 12.1, Safari 15.2, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing maliciously crafted web content may lead to arbitrary code execution.

Severity

CVSS 3.1 · CISA8.8 HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
Apple	watchOS	unspecified to <8.3
Apple	iOS and iPadOS	unspecified to <15.2
Apple	macOS	unspecified to <12.1
Apple	macOS	unspecified to <15.2
Apple	macOS	unspecified to <15.2

References

10 Links

Vendor advisories

Mailing lists

[oss-security] 20220121 WebKitGTK and WPE WebKit Security Advisory WSA-2022-0001

Other references

Record Details

Published

2021-08-24

Last updated

2026-03-06

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.