CVE-2021-30666

HighCVSS 8.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

Description

A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 12.5.3. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-119

Affected software

VendorProductVersions
AppleiOS>= unspecified, < 12.5

References

Timeline

Published
Sep 8, 2021
Last modified
Jun 17, 2026
Added to CISA KEV
Nov 3, 2021
NVD status
Analyzed

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CVE-2021-30666: High severity, CVSS 8.8 | Vulnix